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class="vector-toc-numb">1.4</span> <span>Improved models</span> </div> </a> <ul id="toc-Improved_models-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Design_principles" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Design_principles"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Design principles</span> </div> </a> <button aria-controls="toc-Design_principles-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Design principles subsection</span> </button> <ul id="toc-Design_principles-sublist" class="vector-toc-list"> <li id="toc-Condition_codes" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Condition_codes"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Condition codes</span> </div> </a> <ul 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class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Instruction_formats"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Instruction formats</span> </div> </a> <ul id="toc-Instruction_formats-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Instruction_set" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Instruction_set"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Instruction set</span> </div> </a> <button aria-controls="toc-Instruction_set-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Instruction set subsection</span> </button> <ul id="toc-Instruction_set-sublist" class="vector-toc-list"> <li id="toc-Control_instructions" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Control_instructions"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.1</span> <span>Control instructions</span> </div> </a> <ul id="toc-Control_instructions-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Integer_arithmetic" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Integer_arithmetic"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.2</span> <span>Integer arithmetic</span> </div> </a> <ul id="toc-Integer_arithmetic-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Logical_and_shift" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Logical_and_shift"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.3</span> <span>Logical and shift</span> </div> </a> <ul id="toc-Logical_and_shift-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Extensions" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Extensions"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Extensions</span> </div> </a> <button aria-controls="toc-Extensions-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Extensions subsection</span> </button> <ul id="toc-Extensions-sublist" class="vector-toc-list"> <li id="toc-Byte-Word_Extensions_(BWX)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Byte-Word_Extensions_(BWX)"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.1</span> <span>Byte-Word Extensions (BWX)</span> </div> </a> <ul id="toc-Byte-Word_Extensions_(BWX)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Motion_Video_Instructions_(MVI)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Motion_Video_Instructions_(MVI)"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.2</span> <span>Motion Video Instructions (MVI)</span> </div> </a> <ul id="toc-Motion_Video_Instructions_(MVI)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Floating-point_Extensions_(FIX)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Floating-point_Extensions_(FIX)"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.3</span> <span>Floating-point Extensions (FIX)</span> </div> </a> <ul id="toc-Floating-point_Extensions_(FIX)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Count_Extensions_(CIX)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Count_Extensions_(CIX)"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.4</span> <span>Count Extensions (CIX)</span> </div> </a> <ul id="toc-Count_Extensions_(CIX)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Implementations" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Implementations"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>Implementations</span> </div> </a> <button aria-controls="toc-Implementations-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Implementations subsection</span> </button> <ul id="toc-Implementations-sublist" class="vector-toc-list"> <li id="toc-Model_history" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Model_history"> <div class="vector-toc-text"> <span class="vector-toc-numb">9.1</span> <span>Model history</span> </div> </a> <ul id="toc-Model_history-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Performance" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Performance"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Performance</span> </div> 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id="toc-Notes" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">13</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">14</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header 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class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">DEC Alpha</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 23 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-23" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">23 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="DEC Alpha" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Czech" lang="cs" hreflang="cs" data-title="DEC Alpha" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Alpha-Prozessor" title="Alpha-Prozessor – German" lang="de" hreflang="de" data-title="Alpha-Prozessor" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Spanish" lang="es" hreflang="es" data-title="DEC Alpha" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Alpha" title="Alpha – Esperanto" lang="eo" hreflang="eo" data-title="Alpha" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Basque" lang="eu" hreflang="eu" data-title="DEC Alpha" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%AF%DA%A9_%D8%A2%D9%84%D9%81%D8%A7" title="دک آلفا – Persian" lang="fa" hreflang="fa" data-title="دک آلفا" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – French" lang="fr" hreflang="fr" data-title="DEC Alpha" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/DEC_%EC%95%8C%ED%8C%8C" title="DEC 알파 – Korean" lang="ko" hreflang="ko" data-title="DEC 알파" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Alpha_AXP" title="Alpha AXP – Indonesian" lang="id" hreflang="id" data-title="Alpha AXP" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Italian" lang="it" hreflang="it" data-title="DEC Alpha" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Hungarian" lang="hu" hreflang="hu" data-title="DEC Alpha" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Dutch" lang="nl" hreflang="nl" data-title="DEC Alpha" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Japanese" lang="ja" hreflang="ja" data-title="DEC Alpha" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="DEC Alpha" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Polish" lang="pl" hreflang="pl" data-title="DEC Alpha" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Portuguese" lang="pt" hreflang="pt" data-title="DEC Alpha" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Russian" lang="ru" hreflang="ru" data-title="DEC Alpha" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Finnish" lang="fi" hreflang="fi" data-title="DEC Alpha" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Swedish" lang="sv" hreflang="sv" data-title="DEC Alpha" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Alfa_i%C5%9Flemcisi" title="Alfa işlemcisi – Turkish" lang="tr" hreflang="tr" data-title="Alfa işlemcisi" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Ukrainian" lang="uk" hreflang="uk" data-title="DEC Alpha" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/DEC_Alpha" title="DEC Alpha – Chinese" lang="zh" hreflang="zh" data-title="DEC Alpha" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q858065#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/DEC_Alpha" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:DEC_Alpha" rel="discussion" title="Discuss improvements to the content page 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class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">64-bit RISC instruction set architecture</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox"><caption class="infobox-title">Alpha</caption><tbody><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:DEC_Alpha_Generation_logo.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/86/DEC_Alpha_Generation_logo.svg/220px-DEC_Alpha_Generation_logo.svg.png" decoding="async" width="220" height="144" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/86/DEC_Alpha_Generation_logo.svg/330px-DEC_Alpha_Generation_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/86/DEC_Alpha_Generation_logo.svg/440px-DEC_Alpha_Generation_logo.svg.png 2x" data-file-width="2500" data-file-height="1634" /></a></span><div class="infobox-caption">"Alpha Generation" logo used by Digital</div></td></tr><tr><th scope="row" class="infobox-label">Designer</th><td class="infobox-data"><a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a></td></tr><tr><th scope="row" class="infobox-label">Bits</th><td class="infobox-data"><a href="/wiki/64-bit_computing" title="64-bit computing">64-bit</a></td></tr><tr><th scope="row" class="infobox-label">Introduced</th><td class="infobox-data">1992<span class="noprint">; 33 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">1992</span>)</span></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Computer_architecture" title="Computer architecture">Design</a></th><td class="infobox-data"><a href="/wiki/Reduced_instruction_set_computer" title="Reduced instruction set computer">RISC</a></td></tr><tr><th scope="row" class="infobox-label">Type</th><td class="infobox-data"><a href="/wiki/Load%E2%80%93store" class="mw-redirect" title="Load–store">Load–store</a></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Instruction_set" class="mw-redirect" title="Instruction set">Encoding</a></th><td class="infobox-data">Fixed</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Endianness" title="Endianness">Endianness</a></th><td class="infobox-data"><a href="/wiki/Endianness#Bi-endianness" title="Endianness">Bi</a></td></tr><tr><th scope="row" class="infobox-label">Extensions</th><td class="infobox-data">Byte/Word Extension (BWX), Square-root and Floating-point Convert Extension (FIX), Count Extension (CIX), Motion Video Instructions (MVI)</td></tr><tr><th scope="row" class="infobox-label">Open</th><td class="infobox-data">Yes<sup id="cite_ref-facts_and_comments_1-0" class="reference"><a href="#cite_note-facts_and_comments-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td></tr><tr><th colspan="2" class="infobox-header"><a href="/wiki/Processor_register" title="Processor register">Registers</a></th></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/General-purpose_register" class="mw-redirect" title="General-purpose register">General-purpose</a></th><td class="infobox-data">31 plus always-zero R31</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Floating_point" class="mw-redirect" title="Floating point">Floating point</a></th><td class="infobox-data">31 plus always-0.0 F31</td></tr></tbody></table> <style data-mw-deduplicate="TemplateStyles:r1273380762/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner span:not(.skin-invert-image):not(.skin-invert):not(.bg-transparent) img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner span:not(.skin-invert-image):not(.skin-invert):not(.bg-transparent) img{background-color:white}}</style><div class="thumb tmulti tright"><div class="thumbinner multiimageinner" style="width:244px;max-width:244px"><div class="trow"><div class="theader">Alpha microprocessors</div></div><div class="trow"><div class="tsingle" style="width:242px;max-width:242px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Alpha_AXP_21064_diephoto1.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/92/Alpha_AXP_21064_diephoto1.jpg/240px-Alpha_AXP_21064_diephoto1.jpg" decoding="async" width="240" height="291" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/92/Alpha_AXP_21064_diephoto1.jpg/360px-Alpha_AXP_21064_diephoto1.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/9/92/Alpha_AXP_21064_diephoto1.jpg 2x" data-file-width="454" data-file-height="550" /></a></span></div><div class="thumbcaption">DEC AXP 21064 die photo</div></div></div><div class="trow"><div class="tsingle" style="width:242px;max-width:242px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:DEC_Alpha_21-35023-13_J40793-28_top.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ed/DEC_Alpha_21-35023-13_J40793-28_top.jpg/250px-DEC_Alpha_21-35023-13_J40793-28_top.jpg" decoding="async" width="240" height="240" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ed/DEC_Alpha_21-35023-13_J40793-28_top.jpg/500px-DEC_Alpha_21-35023-13_J40793-28_top.jpg 1.5x" data-file-width="930" data-file-height="930" /></a></span></div><div class="thumbcaption">DEC AXP 21064 package</div></div></div><div class="trow"><div class="tsingle" style="width:242px;max-width:242px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Alpha_AXP_21064_card1.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Alpha_AXP_21064_card1.jpg/240px-Alpha_AXP_21064_card1.jpg" decoding="async" width="240" height="131" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Alpha_AXP_21064_card1.jpg/360px-Alpha_AXP_21064_card1.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/90/Alpha_AXP_21064_card1.jpg/480px-Alpha_AXP_21064_card1.jpg 2x" data-file-width="1264" data-file-height="692" /></a></span></div><div class="thumbcaption">DEC AXP 21064 bare die mounted on business card with some statistics</div></div></div><div class="trow"><div class="tsingle" style="width:242px;max-width:242px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:KL_Compaq_DEC_ALPHA_21264C.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/KL_Compaq_DEC_ALPHA_21264C.jpg/250px-KL_Compaq_DEC_ALPHA_21264C.jpg" decoding="async" width="240" height="240" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/KL_Compaq_DEC_ALPHA_21264C.jpg/500px-KL_Compaq_DEC_ALPHA_21264C.jpg 1.5x" data-file-width="1700" data-file-height="1700" /></a></span></div><div class="thumbcaption">Compaq 21264C</div></div></div></div></div> <p><b>Alpha</b> (original name <b>Alpha AXP</b>) is a <a href="/wiki/64-bit_computing" title="64-bit computing">64-bit</a> <a href="/wiki/Reduced_instruction_set_computer" title="Reduced instruction set computer">reduced instruction set computer</a> (RISC) <a href="/wiki/Instruction_set_architecture" title="Instruction set architecture">instruction set architecture</a> (ISA) developed by <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> (DEC). Alpha was designed to replace <a href="/wiki/32-bit_computing" title="32-bit computing">32-bit</a> <a href="/wiki/VAX" title="VAX">VAX</a> <a href="/wiki/Complex_instruction_set_computer" title="Complex instruction set computer">complex instruction set computers</a> (CISC) and to be a highly competitive RISC processor for <a href="/wiki/Unix_workstation" class="mw-redirect" title="Unix workstation">Unix workstations</a> and similar markets. </p><p>Alpha was implemented in a series of <a href="/wiki/Microprocessor" title="Microprocessor">microprocessors</a> originally developed and <a href="/wiki/Semiconductor_device_fabrication" title="Semiconductor device fabrication">fabricated</a> by DEC. These microprocessors were most prominently used in a variety of DEC workstations and servers, which eventually formed the basis for almost all of their mid-to-upper-scale lineup. Several third-party vendors also produced Alpha systems, including <a href="/wiki/PC_motherboard_form_factor" class="mw-redirect" title="PC motherboard form factor">PC form factor</a> motherboards. </p><p><a href="/wiki/Operating_system" title="Operating system">Operating systems</a> that support Alpha included <a href="/wiki/OpenVMS" title="OpenVMS">OpenVMS</a> (formerly named OpenVMS AXP), <a href="/wiki/Tru64_UNIX" title="Tru64 UNIX">Tru64 UNIX</a> (formerly named DEC OSF/1 AXP and Digital UNIX), <a href="/wiki/Windows_NT" title="Windows NT">Windows NT</a> (discontinued after <a href="/wiki/Windows_NT_4.0" title="Windows NT 4.0">NT 4.0</a>; and prerelease <a href="/wiki/Windows_2000" title="Windows 2000">Windows 2000</a> <a href="/wiki/Software_release_life_cycle" title="Software release life cycle">RC2</a>),<sup id="cite_ref-alphant_2-0" class="reference"><a href="#cite_note-alphant-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Linux" title="Linux">Linux</a> (<a href="/wiki/Debian" title="Debian">Debian</a>, <a href="/wiki/SUSE_Linux" class="mw-redirect" title="SUSE Linux">SUSE</a>,<sup id="cite_ref-alphaSUSE_3-0" class="reference"><a href="#cite_note-alphaSUSE-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Gentoo_Linux" title="Gentoo Linux">Gentoo</a> and <a href="/wiki/Red_Hat_Linux" title="Red Hat Linux">Red Hat</a>), <a href="/wiki/Berkeley_Software_Distribution" title="Berkeley Software Distribution">BSD</a> UNIX (<a href="/wiki/NetBSD" title="NetBSD">NetBSD</a>, <a href="/wiki/OpenBSD" title="OpenBSD">OpenBSD</a> and <a href="/wiki/FreeBSD" title="FreeBSD">FreeBSD</a> up to 6.x), <a href="/wiki/Plan_9_from_Bell_Labs" title="Plan 9 from Bell Labs">Plan 9 from Bell Labs</a>, and the <a href="/wiki/L4_microkernel_family" title="L4 microkernel family">L4Ka::Pistachio</a> kernel. A port of <a href="/wiki/Ultrix" title="Ultrix">Ultrix</a> to Alpha was carried out during the initial development of the Alpha architecture, but was never released as a product.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>The Alpha architecture was sold, along with most parts of DEC, to <a href="/wiki/Compaq" title="Compaq">Compaq</a> in 1998.<sup id="cite_ref-Reg.98_5-0" class="reference"><a href="#cite_note-Reg.98-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Compaq, already an <a href="/wiki/Intel" title="Intel">Intel</a> x86 customer, announced that they would phase out Alpha in favor of the forthcoming <a href="/wiki/Hewlett-Packard" title="Hewlett-Packard">Hewlett-Packard</a>/Intel <a href="/wiki/Itanium" title="Itanium">Itanium</a> architecture, and sold all Alpha <a href="/wiki/Intellectual_property" title="Intellectual property">intellectual property</a> to Intel, in 2001,<sup id="cite_ref-zdnet-compaq_6-0" class="reference"><a href="#cite_note-zdnet-compaq-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> effectively killing the product. Hewlett-Packard purchased Compaq in 2002, continuing development of the existing product line until 2004, and selling Alpha-based systems, largely to the existing customer base, until April 2007.<sup id="cite_ref-alphasupportend_7-0" class="reference"><a href="#cite_note-alphasupportend-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="PRISM">PRISM</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=2" title="Edit section: PRISM"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/DEC_PRISM" title="DEC PRISM">DEC PRISM</a></div> <p>Alpha emerged from an earlier RISC project named Parallel Reduced Instruction Set Machine (<a href="/wiki/DEC_PRISM" title="DEC PRISM">PRISM</a>), itself the product of several earlier projects. PRISM was intended to be a flexible design, supporting Unix-like applications, and Digital's existing VAX/VMS software, after minor conversion. A new <a href="/wiki/Operating_system" title="Operating system">operating system</a> named <a href="/wiki/DEC_MICA" title="DEC MICA">MICA</a> would support both <a href="/wiki/ULTRIX" class="mw-redirect" title="ULTRIX">ULTRIX</a> and VAX/VMS interfaces on a common <a href="/wiki/Kernel_(operating_system)" title="Kernel (operating system)">kernel</a>, allowing software for both platforms to be easily ported to the PRISM architecture.<sup id="cite_ref-mica-business-plan_8-0" class="reference"><a href="#cite_note-mica-business-plan-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>Started in 1985, the PRISM design was continually changed during its development in response to changes in the computer market, leading to lengthy delays in its introduction. It was not until the summer of 1987 that it was decided that it would be a <a href="/wiki/64-bit_computing" title="64-bit computing">64-bit</a> design, among the earliest such designs in a <a href="/wiki/Microprocessor" title="Microprocessor">microprocessor</a> format. In October 1987, <a href="/wiki/Sun_Microsystems" title="Sun Microsystems">Sun Microsystems</a> introduced the <a href="/wiki/Sun-4" title="Sun-4">Sun-4</a>, their first <a href="/wiki/Workstation" title="Workstation">workstation</a> using their new <a href="/wiki/SPARC" title="SPARC">SPARC</a> processor. The Sun-4 runs about three to four times as fast as their latest <a href="/wiki/Sun-3" title="Sun-3">Sun-3</a> designs using the <a href="/wiki/Motorola_68020" title="Motorola 68020">Motorola 68020</a>, and any Unix offering from DEC. The plans changed again; PRISM was realigned once again as a 32-bit part and aimed directly at the Unix market. This further delayed the design.<sup id="cite_ref-microprism_9-0" class="reference"><a href="#cite_note-microprism-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p><p>Having watched the PRISM delivery date continue to slip, and facing the possibility of more delays, a team in the Palo Alto office decided to design their own workstation using another RISC processor. After <a href="/wiki/Due_diligence" title="Due diligence">due diligence</a>, they selected the <a href="/wiki/R2000_(microprocessor)" class="mw-redirect" title="R2000 (microprocessor)">MIPS R2000</a> and built a working workstation running Ultrix in a period of 90 days.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> This sparked off an acrimonious debate within the company, which came to a head in a July 1988 management meeting. PRISM appeared to be faster than the R2000, but the R2000 machines could be in the market by January 1989, a year earlier than PRISM. When this proposal was accepted, one of the two original roles for PRISM disappeared. The decision to make a VMS PRISM had already ended by this point, so there was no remaining role. PRISM was cancelled at the meeting.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="RISCy_VAX">RISCy VAX</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=3" title="Edit section: RISCy VAX"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As the meeting broke up, Bob Supnik was approached by <a href="/wiki/Ken_Olsen" title="Ken Olsen">Ken Olsen</a>, who stated that the RISC chips appeared to be a future threat to their VAX line. He asked Supnik to consider what might be done with VAX to keep it competitive with future RISC systems.<sup id="cite_ref-microprism_9-1" class="reference"><a href="#cite_note-microprism-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p><p>This led to the formation of the "RISCy VAX" team. They initially considered three concepts. One was a cut-down version of the VAX <a href="/wiki/Instruction_set_architecture" title="Instruction set architecture">instruction set architecture</a> (ISA) that would run on a RISC-like system and leave more complex VAX instructions to system subroutines. Another concept was a pure RISC system that would translate existing VAX code into its own ISA on-the-fly and store it in a <a href="/wiki/CPU_cache" title="CPU cache">CPU cache</a>. Finally, there was still the possibility of a much faster CISC processor running the complete VAX ISA. Unfortunately, all of these approaches introduced overhead and would not be competitive with a pure-RISC machine running native RISC code.<sup id="cite_ref-comerford_12-0" class="reference"><a href="#cite_note-comerford-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>The group then considered hybrid systems that combined one of their existing VAX one-chip solution and a RISC chip as a coprocessor used for high-performance needs. These studies suggested that the system would inevitably be hamstrung by the lower-performance part and would offer no compelling advantage. It was at this point that Nancy Kronenberg pointed out that people ran VMS, not VAX, and that VMS only had a few hardware dependencies based on its modelling of <a href="/wiki/Interrupt" title="Interrupt">interrupts</a> and memory paging. There appeared to be no compelling reason why VMS could not be ported to a RISC chip as long as these small bits of the model were preserved. Further work on this concept suggested this was a workable approach.<sup id="cite_ref-comerford_12-1" class="reference"><a href="#cite_note-comerford-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>Supnik took the resulting report to the Strategy Task Force in February 1989. Two questions were raised: could the resulting RISC design also be a performance leader in the Unix market, and should the machine be an open standard? And with that, the decision was made to adopt the PRISM architecture with the appropriate modifications. This became the "EVAX" concept, a follow-on to the successful CMOS <a href="/wiki/CVAX" title="CVAX">CVAX</a> implementation. When management accepted the findings, they decided to give the project a more neutral name, removing "VAX", eventually settling on Alpha.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> The name was inspired by the use of "Omega" as the codename of an <a href="/wiki/NVAX" title="NVAX">NVAX</a>-based <a href="/wiki/VAX_4000" title="VAX 4000">VAX 4000</a> model; "Alpha" was intended to signify the beginning of a new line (with reference to <a href="/wiki/Alpha_and_Omega" title="Alpha and Omega">Alpha and Omega</a>).<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> Soon after, work began on <a href="/wiki/OpenVMS#Port_to_Alpha" title="OpenVMS">a port of VMS to the new architecture</a>.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Alpha">Alpha</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=4" title="Edit section: Alpha"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The new design uses most of the basic PRISM concepts, but was re-tuned to allow VMS and VMS programs to run at reasonable speed with no conversion at all. The primary Alpha instruction set architects were Richard L. Sites and Richard T. Witek.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> The PRISM's Epicode was developed into the Alpha's <a href="/wiki/PALcode" title="PALcode">PALcode</a>, providing an abstracted interface to platform- and processor implementation-specific features. </p><p>The main contribution of Alpha to the microprocessor industry, and the main reason for its performance, is not so much the architecture but rather its implementation.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> At that time (as it is now), the microchip industry was dominated by automated design and layout tools. The chip designers at Digital continued pursuing sophisticated manual circuit design in order to deal with the complex VAX architecture. The Alpha chips show that manual circuit design applied to a simpler, cleaner architecture allows for much higher operating frequencies than those that are possible with the more automated design systems. These chips caused a renaissance of custom circuit design within the microprocessor design community. </p><p>Originally, the Alpha processors were designated the <i>DECchip 21x64</i> series,<sup id="cite_ref-X21_18-0" class="reference"><a href="#cite_note-X21-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> with "DECchip" replaced in the mid-1990s with "Alpha". The first two digits, "21" signifies the 21st century, and the last two digits, "64" signifies 64 bits.<sup id="cite_ref-X21_18-1" class="reference"><a href="#cite_note-X21-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> The Alpha was designed as 64-bit from the start and there is no 32-bit version. The middle digit corresponds to the generation of the Alpha architecture. Internally, Alpha processors were also identified by <i>EV</i> numbers, EV officially standing for "Extended VAX" but having an alternative humorous meaning of "Electric <a href="/wiki/Vlasic_Pickles" title="Vlasic Pickles">Vlasic</a>", giving homage to the <a href="/wiki/Glowing_pickle_demonstration" title="Glowing pickle demonstration">Electric Pickle</a> experiment at Western Research Lab.<sup id="cite_ref-pickle_19-0" class="reference"><a href="#cite_note-pickle-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> The number in the EV designations indicated the semiconductor process which the chip was designed for. For example, the EV4 processor used DEC's CMOS-4 process.<sup id="cite_ref-comerford_12-2" class="reference"><a href="#cite_note-comerford-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>In May 1997, DEC sued <a href="/wiki/Intel" title="Intel">Intel</a> for allegedly infringing on its Alpha patents in designing the <a href="/wiki/Original_Intel_Pentium_(P5_microarchitecture)" class="mw-redirect" title="Original Intel Pentium (P5 microarchitecture)">original Pentium</a>, <a href="/wiki/Pentium_Pro" title="Pentium Pro">Pentium Pro</a>, and <a href="/wiki/Pentium_II" title="Pentium II">Pentium II</a> chips.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> As part of a settlement, much of DEC's chip design and fabrication business was sold to Intel. This included DEC's <a href="/wiki/StrongARM" title="StrongARM">StrongARM</a> implementation of the <a href="/wiki/ARM_architecture_family" title="ARM architecture family">ARM computer architecture</a>, which Intel marketed as the <a href="/wiki/Intel_XScale" class="mw-redirect" title="Intel XScale">XScale</a> processors commonly used in <a href="/wiki/Pocket_PC" title="Pocket PC">Pocket PCs</a>. The core of Digital Semiconductor, the Alpha microprocessor group, remained with DEC, while the associated office buildings went to Intel as part of the Hudson fab.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Improved_models">Improved models</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=5" title="Edit section: Improved models"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first few generations of the Alpha chips were some of the most innovative of their time. </p> <ul><li>A pre-production model, designated <i>EV3</i>, was used in a prototype system named the <i>Alpha Demonstration Unit</i> (ADU). ADUs were used to port operating systems to the Alpha architecture. One key difference between the EV3 and later models was the absence of a floating-point unit.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup></li> <li>The first version, the <i><a href="/wiki/Alpha_21064" title="Alpha 21064">Alpha 21064</a></i> or <i>EV4</i>, is the first <a href="/wiki/CMOS" title="CMOS">CMOS</a> microprocessor whose operating frequency rivalled higher-powered <a href="/wiki/Emitter_coupled_logic" class="mw-redirect" title="Emitter coupled logic">ECL</a> minicomputers and mainframes.</li> <li>The second, <i>21164</i> or <i>EV5</i>, is the first microprocessor to place a large secondary cache on-chip.<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup></li> <li>The third, <i>21264</i> or <i>EV6</i>, is the first microprocessor to combine both high operating frequency and the more complicated <a href="/wiki/Out-of-order_execution" title="Out-of-order execution">out-of-order execution</a> microarchitecture.</li> <li>The <i>21364</i> or <i>EV7</i> is the first high performance processor to have an on-chip <a href="/wiki/Memory_controller" title="Memory controller">memory controller</a>.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup></li> <li>The unproduced <i><a href="/wiki/Alpha_21464" title="Alpha 21464">21464</a></i> or <i>EV8</i> would have been the first to include <a href="/wiki/Simultaneous_multithreading" title="Simultaneous multithreading">simultaneous multithreading</a>, but this version was canceled after the sale of DEC to <a href="/wiki/Compaq" title="Compaq">Compaq</a>. The <i><a href="/wiki/Alpha_21464#Tarantula" title="Alpha 21464">Tarantula</a></i> research project, which most likely would have been called <i>EV9</i>, would have been the first Alpha processor to feature a <a href="/wiki/Vector_processor" title="Vector processor">vector processor</a> unit.<sup id="cite_ref-Tarantula_25-0" class="reference"><a href="#cite_note-Tarantula-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup></li></ul> <p>A persistent report attributed to DEC insiders suggests the choice of the <i>AXP</i> tag for the processor was made by DEC's legal department, which was still smarting from the <a href="/wiki/Vax_(brand)#Trademark_conflict" title="Vax (brand)">VAX trademark</a> fiasco.<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> After a lengthy search the tag "AXP" was found to be entirely unencumbered. Within the computer industry, a joke got started that the acronym <i>AXP</i> meant "Almost eXactly PRISM".<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Design_principles">Design principles</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=6" title="Edit section: Design principles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha architecture was intended to be a high-performance design. Digital intended the architecture to support a one-thousandfold increase in performance over twenty-five years. To ensure this, any architectural feature that impeded multiple instruction issue, clock rate or multiprocessing was removed. As a result, the Alpha does not have: </p> <ul><li><a href="/wiki/Branch_delay_slot" class="mw-redirect" title="Branch delay slot">Branch delay slots</a></li> <li>Suppressed instructions<sup class="noprint Inline-Template" style="margin-left:0.1em; white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Please_clarify" title="Wikipedia:Please clarify"><span title="Is this referring to instructions in a conditionalbranch delay slot not being executed if the branch is not taken? This is often called nullification, not suppression. (January 2023)">clarification needed</span></a></i>]</sup></li> <li>Byte load or store instructions (later added with the Byte Word Extensions (BWX))<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading3"><h3 id="Condition_codes">Condition codes</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=7" title="Edit section: Condition codes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha does not have <a href="/wiki/Status_register" title="Status register">condition codes</a> for integer instructions<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> to remove a potential bottleneck at the condition status register. Instructions resulting in an overflow, such as adding two numbers whose result does not fit in 64 bits, write the 32 or 64 <a href="/wiki/Least_significant_bit" class="mw-redirect" title="Least significant bit">least significant bits</a> to the destination register. The carry is generated by performing an unsigned compare on the result with either operand to see if the result is smaller than either operand. If the test was true, the value one is written to the least significant bit of the destination register to indicate the condition. </p> <div class="mw-heading mw-heading2"><h2 id="Registers">Registers</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=8" title="Edit section: Registers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="infobox" style="font-size:88%;width:34em;"> <caption>DEC Alpha registers </caption> <tbody><tr> <td> <table style="font-size:88%;"> <tbody><tr> <td style="width:10px; text-align:left;"><sup>6</sup><sub>3</sub> </td> <td style="width:50px; text-align:center;">. . . </td> <td style="width:10px; text-align:right;"><sup>4</sup><sub>7</sub> </td> <td style="width:50px; text-align:center;">. . . </td> <td style="width:10px; text-align:center;"><sup>3</sup><sub>1</sub> </td> <td style="width:50px; text-align:center;">. . . </td> <td style="width:10px; text-align:center;"><sup>1</sup><sub>5</sub> </td> <td style="width:50px; text-align:center;">. . . </td> <td style="width:10px; text-align:center;"><sup>0</sup><sub>1</sub> </td> <td style="width:10px; text-align:center;"><sup>0</sup><sub>0</sub> </td> <td style="width:auto; background:white; color:black"><i>(bit position)</i> </td></tr> <tr> <td colspan="11"><b>General-purpose registers</b><br /> </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">R0 </td> <td style="background:white; color:black;">R0 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">R1 </td> <td style="background:white; color:black;">R1 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">R2 </td> <td style="background:white; color:black;">R2 </td></tr> <tr> <td style="text-align:center;" colspan="10">• </td> <td style="background:white; color:black;">  </td></tr> <tr> <td style="text-align:center;" colspan="10">• </td> <td style="background:white; color:black;">  </td></tr> <tr> <td style="text-align:center;" colspan="10">• </td> <td style="background:white; color:black;">  </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">R29 </td> <td style="background:white; color:black;">R29 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">R30 </td> <td style="background:white; color:black;">R30 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10"><span aria-hidden="true" style="visibility:hidden;color:transparent;"><i>(zero)</i></span>R31 <i>(zero)</i> </td> <td style="background:white; color:black; white-space: nowrap">R31, always zero </td></tr> <tr> <td colspan="11"><b>Floating-point registers</b><br /> </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">F0 </td> <td style="background:white; color:black;">F0 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">F1 </td> <td style="background:white; color:black;">F1 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">F2 </td> <td style="background:white; color:black;">F2 </td></tr> <tr> <td style="text-align:center;" colspan="10">• </td> <td style="background:white; color:black;">  </td></tr> <tr> <td style="text-align:center;" colspan="10">• </td> <td style="background:white; color:black;">  </td></tr> <tr> <td style="text-align:center;" colspan="10">• </td> <td style="background:white; color:black;">  </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">F29 </td> <td style="background:white; color:black;">F29 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">F30 </td> <td style="background:white; color:black;">F30 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10"><span aria-hidden="true" style="visibility:hidden;color:transparent;"><i>(zero)</i></span>F31 <i>(zero)</i> </td> <td style="background:white; color:black">F31, always zero </td></tr> <tr> <td colspan="11"><b>Program counter</b> </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;padding-left:2.5em" colspan="8">PC </td> <td style="text-align:center;" colspan="1">0 </td> <td style="text-align:center;" colspan="1">0 </td> <td style="background:white; color:black;"><b>P</b>rogram <b>C</b>ounter </td></tr> <tr> <td colspan="11"><b>Control registers</b><br /> </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">LR0 </td> <td style="background:white; color:black;"><b>L</b>ock <b>R</b>egister 0 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">LR1 </td> <td style="background:white; color:black;"><b>L</b>ock <b>R</b>egister 1 </td></tr> <tr style="background:silver;color:black"> <td style="text-align:center;" colspan="10">FPCR </td> <td style="background:white; color:black;"><b>FP</b> <b>C</b>ontrol <b>R</b>egister </td></tr></tbody></table> </td></tr></tbody></table> <p>The architecture defines a set of 32 integer <a href="/wiki/Processor_register" title="Processor register">registers</a> and a set of 32 floating-point registers in addition to a <a href="/wiki/Program_counter" title="Program counter">program counter</a>, two lock registers and a floating-point control register (FPCR). It also defines registers that were optional, implemented only if the implementation required them. Lastly, registers for <a href="/wiki/PALcode" title="PALcode">PALcode</a> are defined. </p><p>The integer registers are denoted by R0 to R31 and floating-point registers are denoted by F0 to F31. The R31 and F31 registers are hardwired to zero and writes to those registers by instructions are ignored. Digital considered using a combined register file, but a split register file was determined to be better, as it enables two-chip implementations to have a register file located on each chip and integer-only implementations to omit the floating-point register file containing the floating-point registers. A split register file was also determined to be more suitable for multiple instruction issue due to the reduced number of read and write ports. The number of registers per register file was also considered, with 32 and 64 being contenders. Digital concluded that 32 registers was more suitable as it required less <a href="/wiki/Die_(integrated_circuit)" title="Die (integrated circuit)">die</a> space, which improves clock frequencies. This number of registers was deemed not to be a major issue in respect to performance and future growth, as thirty-two registers could support at least eight-way instruction issue. </p><p>The <a href="/wiki/Program_counter" title="Program counter">program counter</a> is a 64-bit register which contains a longword-aligned virtual byte address, that is, the low two bits of the program counter are always zero. The PC is incremented by four to the address of the next instruction when an instruction is decoded. A lock flag and locked physical address register are used by the load-locked and store-conditional instructions for multiprocessor support. The floating-point control register (FPCR) is a 64-bit register defined by the architecture intended for use by Alpha implementations with <a href="/wiki/IEEE_754" title="IEEE 754">IEEE 754</a>-compliant floating-point hardware. </p> <div class="mw-heading mw-heading2"><h2 id="Data_types">Data types</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=9" title="Edit section: Data types"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the Alpha architecture, a <i><a href="/wiki/Byte" title="Byte">byte</a></i> is defined as an <a href="/wiki/8-bit_computing" title="8-bit computing">8-bit</a> <a href="/wiki/Data_(computing)" class="mw-redirect" title="Data (computing)">datum</a> (octet), a <i><a href="/wiki/Word_(data_type)" class="mw-redirect" title="Word (data type)">word</a></i> as a <a href="/wiki/16-bit_computing" title="16-bit computing">16-bit</a> datum, a <i><a href="/wiki/Longword" class="mw-redirect" title="Longword">longword</a></i> as a <a href="/wiki/32-bit_computing" title="32-bit computing">32-bit</a> datum, a <i><a href="/wiki/Quadword" class="mw-redirect" title="Quadword">quadword</a></i> as a <a href="/wiki/64-bit_computing" title="64-bit computing">64-bit</a> datum, and an <i><a href="/wiki/Octaword" class="mw-redirect" title="Octaword">octaword</a></i> as a <a href="/wiki/128-bit_computing" title="128-bit computing">128-bit</a> datum. </p><p>The Alpha architecture originally defined six data types: </p> <ul><li>Quadword (64-bit) integer</li> <li>Longword (32-bit) integer</li> <li>IEEE T-floating-point (double precision, 64-bit)</li> <li>IEEE S-floating-point (single precision, 32-bit)</li></ul> <p>To maintain a level of compatibility with the <a href="/wiki/VAX" title="VAX">VAX</a>, the 32-bit architecture that preceded the Alpha, two other floating-point data types are included: </p> <ul><li>VAX G-floating point (double precision, 64-bit)</li> <li>VAX F-floating point (single precision, 32-bit)</li></ul> <p>VAX H-floating point (quad precision, 128-bit) was not supported,<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> but another 128-bit floating-point option, X-floating point, is available on Alpha, but not VAX.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup><br />H and X have been described as similar, but not identical. Software emulation for H-floating is available from DEC, as is a source-code level converter named DECmigrate. </p> <div class="mw-heading mw-heading2"><h2 id="Memory">Memory</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=10" title="Edit section: Memory"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha has a 64-bit linear <a href="/wiki/Virtual_address" class="mw-redirect" title="Virtual address">virtual address</a> space with no memory segmentation. Implementations can implement a smaller virtual address space with a minimum size of 43 bits. Although the unused bits were not implemented in hardware such as <a href="/wiki/Translation_lookaside_buffer" title="Translation lookaside buffer">TLBs</a>, the architecture required implementations to check whether they are zero to ensure software compatibility with implementations with a larger (or full) virtual address space. </p> <div class="mw-heading mw-heading2"><h2 id="Instruction_formats">Instruction formats</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=11" title="Edit section: Instruction formats"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha ISA has a fixed instruction length of 32 bits. It has six instruction formats. </p> <table class="wikitable" style="text-align:center;"> <tbody><tr> <td style="background-color:#DDDDFF"><b>Type</b> </td> <td width="15px">31 </td> <td width="15px">30 </td> <td width="15px">29 </td> <td width="15px">28 </td> <td width="15px">27 </td> <td width="15px">26 </td> <td width="15px">25 </td> <td width="15px">24 </td> <td width="15px">23 </td> <td width="15px">22 </td> <td width="15px">21 </td> <td width="15px">20 </td> <td width="15px">19 </td> <td width="15px">18 </td> <td width="15px">17 </td> <td width="15px">16 </td> <td width="15px">15 </td> <td width="15px">14 </td> <td width="15px">13 </td> <td width="15px">12 </td> <td width="15px">11 </td> <td width="15px">10 </td> <td width="15px">9 </td> <td width="15px">8 </td> <td width="15px">7 </td> <td width="15px">6 </td> <td width="15px">5 </td> <td width="15px">4 </td> <td width="15px">3 </td> <td width="15px">2 </td> <td width="15px">1 </td> <td width="15px">0 </td></tr> <tr> <td style="background-color:#EEEEFF">Integer operate </td> <td colspan="6">Opcode </td> <td colspan="5">Ra </td> <td colspan="5">Rb </td> <td colspan="3">Unused </td> <td colspan="1">0 </td> <td colspan="7">Function </td> <td colspan="5">Rc </td></tr> <tr> <td style="background-color:#EEEEFF">Integer operate, literal </td> <td colspan="6">Opcode </td> <td colspan="5">Ra </td> <td colspan="8">Literal </td> <td colspan="1">1 </td> <td colspan="7">Function </td> <td colspan="5">Rc </td></tr> <tr> <td style="background-color:#EEEEFF">Floating-point operate </td> <td colspan="6">Opcode </td> <td colspan="5">Ra </td> <td colspan="5">Rb </td> <td colspan="11">Function </td> <td colspan="5">Rc </td></tr> <tr> <td style="background-color:#EEEEFF">Memory format </td> <td colspan="6">Opcode </td> <td colspan="5">Ra </td> <td colspan="5">Rb </td> <td colspan="16">Displacement </td></tr> <tr> <td style="background-color:#EEEEFF">Branch format </td> <td colspan="6">Opcode </td> <td colspan="5">Ra </td> <td colspan="21">Displacement </td></tr> <tr> <td style="background-color:#EEEEFF">CALL_PAL format </td> <td colspan="6">Opcode </td> <td colspan="26">Function </td></tr> </tbody></table> <p>The integer operate format is used by integer instructions. It contains a 6-bit opcode field, followed by the Ra field, which specifies the register containing the first operand and the Rb field, specifies the register containing the second operand. Next is a 3-bit field which is unused and reserved. A 1-bit field contains a "0", which distinguished this format from the integer literal format. A 7-bit function field follows, which is used in conjunction with the opcode to specify an operation. The last field is the Rc field, which specifies the register which the result of a computation should be written to. The register fields are all 5 bits long, required to address 32 unique locations, the 32 integer registers. </p><p>The integer literal format is used by integer instructions which use a literal as one of the operands. The format is the same as the integer operate format except for the replacement of the 5-bit Rb field and the 3 bits of unused space with an 8-bit literal field which is zero-extended to a 64-bit operand. </p><p>The floating-point operate format is used by floating-point instructions. It is similar to the integer operate format, but has an 11-bit function field made possible by using the literal and unused bits which are reserved in integer operate format. </p><p>The memory format is used mostly by load and store instructions. It has a 6-bit opcode field, a 5-bit Ra field, a 5-bit Rb field and a 16-bit displacement field. </p><p>Branch instructions have a 6-bit opcode field, a 5-bit Ra field and a 21-bit displacement field. The Ra field specifies a register to be tested by a conditional branch instruction, and if the condition is met, the program counter is updated by adding the contents of the displacement field with the program counter. The displacement field contains a signed integer and if the value of the integer is positive, if the branch is taken then the program counter is incremented. If the value of the integer is negative, then program counter is decremented if the branch is taken. The range of a branch thus is ±1 Mi instructions, or ±4 MiB. The Alpha Architecture was designed with a large range as part of the architecture's forward-looking goal. </p><p>The CALL_PAL format is used by the <code>CALL_PAL</code> instruction, which is used to call <a href="/wiki/PALcode" title="PALcode">PALcode</a> subroutines. The format retains the opcode field but replaces the others with a 26-bit function field, which contains an integer specifying a PAL subroutine. </p> <div class="mw-heading mw-heading2"><h2 id="Instruction_set">Instruction set</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=12" title="Edit section: Instruction set"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Control_instructions">Control instructions</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=13" title="Edit section: Control instructions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Control_flow" title="Control flow">control</a> instructions consist of conditional and unconditional branches, and jumps. The conditional and unconditional branch instructions use the branch instruction format, while the jump instructions use the memory instruction format. </p><p>Conditional branches test whether the least significant bit of a register is set or clear, or compare a register as a signed quadword to zero, and branch if the specified condition is true. The conditions available for comparing a register to zero are equality, inequality, less than, less than or equal to, greater than or equal to, and greater than. The new address is computed by longword aligning and sign extending the 21-bit displacement and adding it to the address of the instruction following the conditional branch. </p><p>Unconditional branches update the program counter with a new address computed in the same way as conditional branches. They also save the address of the instruction following the unconditional branch to a register. There are two such instructions, and they differ only in the hints provided for the branch prediction hardware. </p><p>There are four jump instructions. These all perform the same operation, saving the address of the instruction following the jump, and providing the program counter with a new address from a register. They differ in the hints provided to the branch prediction hardware. The unused displacement field is used for this purpose. </p> <div class="mw-heading mw-heading3"><h3 id="Integer_arithmetic">Integer arithmetic</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=14" title="Edit section: Integer arithmetic"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The integer arithmetic instructions perform addition, multiplication, and subtraction on longwords and quadwords; and comparison on quadwords. There is no instruction(s) for division as the architects considered the implementation of division in hardware to be adverse to simplicity. In addition to the standard add and subtract instructions, there are <i>scaled</i> versions. These versions shift the second operand to the left by two or three bits before adding or subtracting. The <i>Multiply Longword</i> and <i>Multiply Quadword</i> instructions write the least significant 32 or 64 bits of a 64- or 128-bit result to the destination register, respectively. Since it is useful to obtain the most significant half, the <i>Unsigned Multiply Quadword High</i> (UMULH) instruction is provided. UMULH is used for implementing multi-precision arithmetic and division algorithms. The concept of a separate instruction for multiplication that returns the most significant half of a result was taken from <a href="/wiki/DEC_PRISM" title="DEC PRISM">PRISM</a>. </p><p>The instructions that operate on longwords ignore the most significant half of the register and the 32-bit result is sign-extended before it is written to the destination register. By default, the add, multiply, and subtract instructions, with the exception of UMULH and scaled versions of add and subtract, do not trap on overflow. When such functionality is required, versions of these instructions that perform overflow detection and trap on overflow are provided. </p><p>The compare instructions compare two registers or a register and a literal and write '1' to the destination register if the specified condition is true or '0' if not. The conditions are equality, inequality, less than or equal to, and less than. With the exception of the instructions that specify the former two conditions, there are versions that perform signed and unsigned compares. </p><p>The integer arithmetic instructions use the integer operate instruction formats. </p> <div class="mw-heading mw-heading3"><h3 id="Logical_and_shift">Logical and shift</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=15" title="Edit section: Logical and shift"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The logical instructions consist of those for performing <a href="/wiki/Bitwise_operation" title="Bitwise operation">bitwise</a> logical operations and <a href="/wiki/Conditional_move" class="mw-redirect" title="Conditional move">conditional moves</a> on the integer registers. The bitwise logical instructions perform <a href="/wiki/Logical_conjunction" title="Logical conjunction">AND</a>, <a href="/wiki/Sheffer_stroke" title="Sheffer stroke">NAND</a>, <a href="/wiki/Logical_NOR" title="Logical NOR">NOR</a>, <a href="/wiki/Logical_disjunction" title="Logical disjunction">OR</a>, <a href="/wiki/XNOR" class="mw-redirect" title="XNOR">XNOR</a>, and <a href="/wiki/XOR" class="mw-redirect" title="XOR">XOR</a> between two registers or a register and literal. The conditional move instructions test a register as a signed quadword to zero and move if the specified condition is true. The specified conditions are equality, inequality, less than or equal to, less than, greater than or equal to, and greater than. The shift instructions perform <a href="/wiki/Arithmetic_shift" title="Arithmetic shift">arithmetic right shift</a>, and <a href="/wiki/Logical_shift" title="Logical shift">logical left and right shifts</a>. The shift amount is given by a register or literal. Logical and shift instructions use the integer operate instruction formats. </p> <div class="mw-heading mw-heading2"><h2 id="Extensions">Extensions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=16" title="Edit section: Extensions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Byte-Word_Extensions_(BWX)"><span id="Byte-Word_Extensions_.28BWX.29"></span>Byte-Word Extensions (BWX)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=17" title="Edit section: Byte-Word Extensions (BWX)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Later Alphas include byte-word extensions, a set of instructions to manipulate 8-bit and 16-bit data types. These instructions were first introduced in the <a href="/wiki/Alpha_21164#Alpha_21164_(EV56)" title="Alpha 21164">21164A</a> (EV56) microprocessor and are present in all subsequent implementations. These instructions perform operations that formerly required multiple instructions to implement, which improves code density and the performance of certain applications. BWX also makes the emulation of x86 machine code and the writing of <a href="/wiki/Device_driver" title="Device driver">device drivers</a> easier.<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th width="120">Mnemonic </th> <th width="360">Instruction </th></tr> <tr> <td><code>LDBU</code> </td> <td>Load Zero-Extended Byte from Memory to Register </td></tr> <tr> <td><code>LDWU</code> </td> <td>Load Zero-Extended Word from Memory to Register </td></tr> <tr> <td><code>SEXTB</code> </td> <td>Sign Extend Byte </td></tr> <tr> <td><code>SEXTW</code> </td> <td>Sign Extend Word </td></tr> <tr> <td><code>STB</code> </td> <td>Store Byte from Register to Memory </td></tr> <tr> <td><code>STW</code> </td> <td>Store Word from Register to Memory </td></tr> </tbody></table> <div class="mw-heading mw-heading3"><h3 id="Motion_Video_Instructions_(MVI)"><span id="Motion_Video_Instructions_.28MVI.29"></span>Motion Video Instructions (MVI)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=18" title="Edit section: Motion Video Instructions (MVI)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Motion Video Instructions (MVI) was an instruction set extension to the Alpha ISA that added instructions for <a href="/wiki/Single_instruction,_multiple_data" title="Single instruction, multiple data">single instruction, multiple data</a> (SIMD) operations.<sup id="cite_ref-34" class="reference"><a href="#cite_note-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> Alpha implementations that implement MVI, in chronological order, are the <a href="/wiki/Alpha_21164#Alpha_21164PC" title="Alpha 21164">Alpha 21164PC</a> (PCA56 and PCA57), <a href="/wiki/Alpha_21264" title="Alpha 21264">Alpha 21264</a> (EV6) and <a href="/wiki/Alpha_21364" title="Alpha 21364">Alpha 21364</a> (EV7). Unlike most other SIMD instruction sets of the same period, such as <a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS</a>' <a href="/wiki/MDMX" title="MDMX">MDMX</a> or <a href="/wiki/SPARC" title="SPARC">SPARC</a>'s <a href="/wiki/Visual_Instruction_Set" title="Visual Instruction Set">Visual Instruction Set</a>, but like <a href="/wiki/PA-RISC" title="PA-RISC">PA-RISC</a>'s <a href="/wiki/Multimedia_Acceleration_eXtensions" title="Multimedia Acceleration eXtensions">Multimedia Acceleration eXtensions</a> (MAX-1, MAX-2), MVI was a simple instruction set composed of a few instructions that operate on integer data types stored in existing integer registers. </p><p>MVI's simplicity is due to two reasons. Firstly, Digital had determined that the <a href="/wiki/Alpha_21164" title="Alpha 21164">Alpha 21164</a> was already capable of performing <a href="/wiki/DVD" title="DVD">DVD</a> decoding through software, therefore not requiring hardware provisions for the purpose, but was inefficient in <a href="/wiki/MPEG-2" title="MPEG-2">MPEG-2</a> encoding. The second reason is the requirement to retain the fast cycle times of implementations. Adding many instructions would have complicated and enlarged the instruction decode logic, reducing an implementation's clock frequency. </p><p>MVI consists of 13 instructions: </p> <table class="wikitable"> <tbody><tr> <th width="120">Mnemonic </th> <th width="360">Instruction </th></tr> <tr> <td><code>MAXSB8</code> </td> <td>Vector Signed Byte Maximum </td></tr> <tr> <td><code>MAXSW4</code> </td> <td>Vector Signed Word Maximum </td></tr> <tr> <td><code>MAXUB8</code> </td> <td>Vector Unsigned Byte Maximum </td></tr> <tr> <td><code>MAXUW4</code> </td> <td>Vector Unsigned Word Maximum </td></tr> <tr> <td><code>MINSB8</code> </td> <td>Vector Signed Byte Minimum </td></tr> <tr> <td><code>MINSW4</code> </td> <td>Vector Signed Word Minimum </td></tr> <tr> <td><code>MINUB8</code> </td> <td>Vector Unsigned Byte Minimum </td></tr> <tr> <td><code>MINUW4</code> </td> <td>Vector Unsigned Word Minimum </td></tr> <tr> <td><code>PERR</code> </td> <td>Pixel Error </td></tr> <tr> <td><code>PKLB</code> </td> <td>Pack Longwords to Bytes </td></tr> <tr> <td><code>PKWB</code> </td> <td>Pack Words to Bytes </td></tr> <tr> <td><code>UNPKBL</code> </td> <td>Unpack Bytes to Longwords </td></tr> <tr> <td><code>UNPKBW</code> </td> <td>Unpack Bytes to Words </td></tr> </tbody></table> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul 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style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Multimedia_extensions" title="Template:Multimedia extensions"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Multimedia_extensions" title="Template talk:Multimedia extensions"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Multimedia_extensions" title="Special:EditPage/Template:Multimedia extensions"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Instruction_set_extensions480" style="font-size:114%;margin:0 4em"><a href="/wiki/Instruction_set" class="mw-redirect" title="Instruction set">Instruction set</a> <a href="/wiki/Processor_supplementary_capability" title="Processor supplementary capability">extensions</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Single_instruction,_multiple_data" title="Single instruction, multiple data">SIMD</a> (<a href="/wiki/Reduced_instruction_set_computer" title="Reduced instruction set computer">RISC</a>)</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">Alpha</a> <ul><li><a class="mw-selflink-fragment" href="#Motion_Video_Instructions_(MVI)">MVI</a></li></ul></li> <li><a href="/wiki/ARM_architecture_family" title="ARM architecture family">ARM</a> <ul><li><a href="/wiki/ARM_architecture_family#Advanced_SIMD_(Neon)" title="ARM architecture family">NEON</a></li> <li><a href="/wiki/AArch64#Scalable_Vector_Extension_(SVE)" title="AArch64">SVE</a></li></ul></li> <li><a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS</a> <ul><li><a href="/wiki/MDMX" title="MDMX">MDMX</a></li> <li><a href="/wiki/MIPS-3D" title="MIPS-3D">MIPS-3D</a></li> <li><a href="/wiki/Media_Extension_Unit" class="mw-redirect" title="Media Extension Unit">MXU</a></li> <li><a href="/wiki/MIPS_architecture#MIPS_SIMD_architecture" title="MIPS architecture">MIPS SIMD</a></li></ul></li> <li><a href="/wiki/PA-RISC" title="PA-RISC">PA-RISC</a> <ul><li><a href="/wiki/Multimedia_Acceleration_eXtensions" title="Multimedia Acceleration eXtensions">MAX</a></li></ul></li> <li><a href="/wiki/Power_ISA" title="Power ISA">Power ISA</a> <ul><li><a href="/wiki/AltiVec" title="AltiVec">VMX</a></li></ul></li> <li><a href="/wiki/SPARC" title="SPARC">SPARC</a> <ul><li><a href="/wiki/Visual_Instruction_Set" title="Visual Instruction Set">VIS</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Single_instruction,_multiple_data" title="Single instruction, multiple data">SIMD</a> (<a href="/wiki/X86" title="X86">x86</a>)</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MMX_(instruction_set)" title="MMX (instruction set)">MMX</a> (1996)</li> <li><a href="/wiki/3DNow!" title="3DNow!">3DNow!</a> (1998)</li> <li><a href="/wiki/Streaming_SIMD_Extensions" title="Streaming SIMD Extensions">SSE</a> (1999)</li> <li><a href="/wiki/SSE2" title="SSE2">SSE2</a> (2001)</li> <li><a href="/wiki/SSE3" title="SSE3">SSE3</a> (2004)</li> <li><a href="/wiki/SSSE3" title="SSSE3">SSSE3</a> (2006)</li> <li><a href="/wiki/SSE4" title="SSE4">SSE4</a> (2006)</li> <li><a href="/wiki/SSE5" title="SSE5">SSE5</a> <s>(2007)</s></li> <li><a href="/wiki/Advanced_Vector_Extensions" title="Advanced Vector Extensions">AVX</a> (2008)</li> <li><a href="/wiki/F16C" title="F16C">F16C</a> (2009)</li> <li><a href="/wiki/XOP_instruction_set" title="XOP instruction set">XOP</a> (2009)</li> <li><a href="/wiki/FMA_instruction_set" title="FMA instruction set">FMA</a> (FMA4: 2011, FMA3: 2012)</li> <li><a href="/wiki/AVX2" class="mw-redirect" title="AVX2">AVX2</a> (2013)</li> <li><a href="/wiki/AVX-512" title="AVX-512">AVX-512</a> (2015)</li> <li><a href="/wiki/Advanced_Matrix_Extensions" title="Advanced Matrix Extensions">AMX</a> (2022)</li> <li><a href="/wiki/AVX10" class="mw-redirect" title="AVX10">AVX10</a> (2023)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Bit_manipulation" title="Bit manipulation">Bit manipulation</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bit_Manipulation_Instruction_Sets" class="mw-redirect" title="Bit Manipulation Instruction Sets">BMI</a> (ABM: 2007, BMI1: 2012, BMI2: 2013, TBM: 2012)</li> <li><a href="/wiki/Intel_ADX" title="Intel ADX">ADX</a> (2014)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Instruction_set_architecture#Code_density" title="Instruction set architecture">Compressed instructions</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ARM_architecture_family#Thumb" title="ARM architecture family">Thumb</a></li> <li><a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS16e ASE</a></li> <li><a href="/wiki/RISC-V#Compressed_subset" title="RISC-V">RVC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Security and <a href="/wiki/Cryptographic_accelerator" title="Cryptographic accelerator">cryptography</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/VIA_PadLock" title="VIA PadLock">PadLock</a> (2003)</li> <li><a href="/wiki/AES_instruction_set" title="AES instruction set">AES-NI</a> (2008); ARMv8 also has AES instructions</li> <li><a href="/wiki/CLMUL_instruction_set" title="CLMUL instruction set">CLMUL</a> (2010)</li> <li><a href="/wiki/RDRAND" title="RDRAND">RDRAND</a> (2012)</li> <li><a href="/wiki/Intel_SHA_extensions" class="mw-redirect" title="Intel SHA extensions">SHA</a> (2013)</li> <li><a href="/wiki/Intel_MPX" title="Intel MPX">MPX</a> (2015)</li> <li><a href="/wiki/Software_Guard_Extensions" title="Software Guard Extensions">SGX</a> (2015)</li> <li><a href="/wiki/Trust_Domain_Extensions" title="Trust Domain Extensions">TDX</a> (2021)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Transactional_memory" title="Transactional memory">Transactional memory</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Transactional_Synchronization_Extensions" title="Transactional Synchronization Extensions">TSX</a> (2013)</li> <li><a href="/wiki/Advanced_Synchronization_Facility" title="Advanced Synchronization Facility">ASF</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Hardware-assisted_virtualization" class="mw-redirect" title="Hardware-assisted virtualization">Virtualization</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X86_virtualization#Intel_virtualization_(VT-x)" title="X86 virtualization">VT-x</a> (2005)</li> <li><a href="/wiki/X86_virtualization#AMD_virtualization_(AMD-V)" title="X86 virtualization">AMD-V</a> (2006)</li> <li><a href="/wiki/X86_virtualization#I/O_MMU_virtualization_(AMD-Vi_and_Intel_VT-d)" title="X86 virtualization">VT-d</a> (AMD-Vi)</li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>Suspended extensions' dates are <s>struck through</s>.</div></td></tr></tbody></table></div> <div class="mw-heading mw-heading3"><h3 id="Floating-point_Extensions_(FIX)"><span id="Floating-point_Extensions_.28FIX.29"></span>Floating-point Extensions (FIX)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=19" title="Edit section: Floating-point Extensions (FIX)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Floating-point extensions (FIX) are an extension to the Alpha Architecture. It introduces nine instructions for floating-point square-root and for transferring data to and from the integer registers and floating-point registers. The <a href="/wiki/Alpha_21264" title="Alpha 21264">Alpha 21264</a> (EV6) is the first microprocessor to implement these instructions. </p> <table class="wikitable"> <tbody><tr> <th width="120">Mnemonic </th> <th width="360">Instruction </th></tr> <tr> <td><code>FTOIS</code> </td> <td>Floating-point to Integer Register Move, S_floating </td></tr> <tr> <td><code>FTOIT</code> </td> <td>Floating-point to Integer Register Move, T_floating </td></tr> <tr> <td><code>ITOFF</code> </td> <td>Integer to Floating-point Register Move, F_floating </td></tr> <tr> <td><code>ITOFS</code> </td> <td>Integer to Floating-point Register Move, S_floating </td></tr> <tr> <td><code>ITOFT</code> </td> <td>Integer to Floating-point Register Move, T_floating </td></tr> <tr> <td><code>SQRTF</code> </td> <td>Square root F_floating </td></tr> <tr> <td><code>SQRTG</code> </td> <td>Square root G_floating </td></tr> <tr> <td><code>SQRTS</code> </td> <td>Square root S_floating </td></tr> <tr> <td><code>SQRTT</code> </td> <td>Square root T_floating </td></tr> </tbody></table> <div class="mw-heading mw-heading3"><h3 id="Count_Extensions_(CIX)"><span id="Count_Extensions_.28CIX.29"></span>Count Extensions (CIX)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=20" title="Edit section: Count Extensions (CIX)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Count Extensions (CIX) is an extension to the architecture which introduces three instructions for counting bits. These instructions are categorized as integer arithmetic instructions. They were first implemented on the <a href="/wiki/Alpha_21264#Alpha_21264A" title="Alpha 21264">Alpha 21264A</a> (EV67). </p> <table class="wikitable"> <tbody><tr> <th width="120">Mnemonic </th> <th width="360">Instruction </th></tr> <tr> <td><code>CTLZ</code> </td> <td>Count Leading Zero </td></tr> <tr> <td><code>CTPOP</code> </td> <td>Count Population </td></tr> <tr> <td><code>CTTZ</code> </td> <td>Count Trailing Zero </td></tr> </tbody></table> <div class="mw-heading mw-heading2"><h2 id="Implementations">Implementations</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=21" title="Edit section: Implementations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>At the time of its announcement, Alpha was heralded as an architecture for the next 25 years. While this was not to be, Alpha has nevertheless had a reasonably long life. The first version, the <i><a href="/wiki/Alpha_21064" title="Alpha 21064">Alpha 21064</a></i> (otherwise named the <i>EV4</i>) was introduced in November 1992 running at up to 192 MHz; a slight shrink of the die (the <i>EV4S</i>, shrunk from 0.75 μm to 0.675 μm) ran at 200 MHz a few months later. The 64-bit processor was a <a href="/wiki/Superpipelined" class="mw-redirect" title="Superpipelined">superpipelined</a> and <a href="/wiki/Superscalar" class="mw-redirect" title="Superscalar">superscalar</a> design, like other RISC designs, but nevertheless outperformed them all and DEC touted it as the world's fastest processor. Careful attention to circuit design, a hallmark of the Hudson design team, like a huge centralized clock circuitry, allowed them to run the CPU at higher speeds, even though the microarchitecture was fairly similar to other RISC chips. In comparison, the less expensive <a href="/wiki/Original_Intel_Pentium_(P5_microarchitecture)" class="mw-redirect" title="Original Intel Pentium (P5 microarchitecture)">Intel Pentium</a> ran at 66 MHz when it was launched the following spring. </p><p>The <i><a href="/wiki/Alpha_21164" title="Alpha 21164">Alpha 21164</a></i> or <i>EV5</i> became available in 1995 at processor frequencies of up to 333 MHz. In July 1996 the line was speed bumped to 500 MHz, in March 1998 to 666 MHz. Also in 1998 the <i><a href="/wiki/Alpha_21264" title="Alpha 21264">Alpha 21264</a></i> (<i>EV6</i>) was released at 450 MHz, eventually reaching (in 2001 with the <i>21264C</i>/<i>EV68CB</i>) 1.25 GHz. In 2003, the <i><a href="/wiki/Alpha_21364" title="Alpha 21364">Alpha 21364</a></i> or <i>EV7</i> <i>Marvel</i> was launched, essentially an EV68 core with four 1.6 GB/s<sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>a<span class="cite-bracket">]</span></a></sup> inter-processor communication links for improved <a href="/wiki/Multiprocessor" class="mw-redirect" title="Multiprocessor">multiprocessor</a> system performance, running at 1 or 1.15 GHz. </p><p>In 1996, the production of Alpha chips was licensed to <a href="/wiki/Samsung_Electronics" title="Samsung Electronics">Samsung Electronics Company</a>. Following the purchase of Digital by <a href="/wiki/Compaq" title="Compaq">Compaq</a> the majority of the Alpha products were placed with <a href="/w/index.php?title=API_NetWorks&action=edit&redlink=1" class="new" title="API NetWorks (page does not exist)">API NetWorks</a>, Inc. (formerly Alpha Processor Inc.), a private company funded by Samsung and Compaq. In October 2001, <a href="/w/index.php?title=Microway&action=edit&redlink=1" class="new" title="Microway (page does not exist)">Microway</a> became the exclusive sales and service provider of API NetWorks' Alpha-based product line. </p><p>On June 25, 2001, Compaq announced that Alpha would be phased out by 2004 in favor of <a href="/wiki/Intel" title="Intel">Intel</a>'s <a href="/wiki/Itanium" title="Itanium">Itanium</a>, canceled the planned <i><a href="/wiki/Alpha_21464" title="Alpha 21464">EV8</a></i> chip, and sold all Alpha intellectual property to <a href="/wiki/Intel" title="Intel">Intel</a>.<sup id="cite_ref-zdnet-compaq_6-1" class="reference"><a href="#cite_note-zdnet-compaq-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Hewlett-Packard" title="Hewlett-Packard">Hewlett-Packard</a> merged with Compaq in 2002; HP announced that development of the Alpha series would continue for a few more years, including the release of a 1.3 GHz EV7 variant named the <i>EV7z</i>. This would be the final iteration of Alpha, the 0.13 μm <i>EV79</i> also being canceled. </p><p>Alpha is also implemented in the <i>Piranha</i>, a research prototype developed by Compaq's Corporate Research and Nonstop Hardware Development groups at the Western Research Laboratory and Systems Research Center. <i>Piranha</i> is a <a href="/wiki/Multi-core_processor" title="Multi-core processor">multicore</a> design for <a href="/wiki/Transaction_processing" title="Transaction processing">transaction processing</a> workloads that contains eight simple cores. It was described at the 27th Annual International Symposium on Computer Architecture in June 2000.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p><p>Early revisions of the <a href="/wiki/Sunway_(processor)" title="Sunway (processor)">Sunway</a> architecture are claimed to be based on Alpha, however since the <a href="/wiki/SW26010" class="mw-redirect" title="SW26010">SW26010</a>, Sunway uses a new instruction set architecture unrelated to Alpha.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-dongarra2016_38-0" class="reference"><a href="#cite_note-dongarra2016-38"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Model_history">Model history</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=22" title="Edit section: Model history"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable sortable" style="font-size:97%; text-align:center;"> <tbody><tr> <th>Model </th> <th>Model number </th> <th>Year </th> <th>Frequency [MHz] </th> <th>Process [μm] </th> <th>Transistors [millions] </th> <th>Die size [mm<sup>2</sup>] </th> <th>IO pins </th> <th>Power [W] </th> <th>Voltage </th> <th>Dcache [KB]<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>b<span class="cite-bracket">]</span></a></sup> </th> <th>Icache [KB] </th> <th>Scache </th> <th>Bcache </th> <th><a href="#ISA">ISA</a> </th></tr> <tr> <th>EV4 </th> <td><a href="/wiki/Alpha_21064" title="Alpha 21064">21064</a></td> <td>1992</td> <td>100–200</td> <td>0.75</td> <td>1.68</td> <td>234</td> <td>290</td> <td>30</td> <td>3.3</td> <td>8</td> <td>8</td> <td>–</td> <td>128 KB–16 MB</td> <td>  </td></tr> <tr> <th>EV4S </th> <td>21064</td> <td>1993</td> <td>100–200</td> <td>0.675</td> <td>1.68</td> <td>186</td> <td>290</td> <td>27</td> <td>3.3</td> <td>8</td> <td>8</td> <td>–</td> <td>128 KB–16 MB</td> <td>  </td></tr> <tr> <th>EV45 </th> <td>21064A</td> <td>1994</td> <td>200–300</td> <td>0.5</td> <td>2.85</td> <td>164</td> <td></td> <td>33</td> <td>3.3</td> <td>16</td> <td>16</td> <td>–</td> <td>256 KB–16 MB</td> <td>  </td></tr> <tr> <th>LCA4 </th> <td>21066</td> <td>1993</td> <td>100–166</td> <td>0.675</td> <td>1.75</td> <td>209</td> <td></td> <td>21</td> <td>3.3</td> <td>8</td> <td>8</td> <td>–</td> <td> </td> <td>  </td></tr> <tr> <th>LCA4 </th> <td>21068</td> <td>1994</td> <td>66</td> <td>0.675</td> <td>1.75</td> <td>209</td> <td></td> <td>9</td> <td>3.3</td> <td>8</td> <td>8</td> <td>–</td> <td> </td> <td>  </td></tr> <tr> <th>LCA45 </th> <td>21066A</td> <td>1994</td> <td>100–266</td> <td>0.5</td> <td>1.8</td> <td>161</td> <td></td> <td>23</td> <td>3.3</td> <td>8</td> <td>8</td> <td>–</td> <td> </td> <td>  </td></tr> <tr> <th>LCA45 </th> <td>21068A</td> <td>1994</td> <td>100</td> <td>0.5</td> <td>1.8</td> <td>161</td> <td></td> <td></td> <td>3.3</td> <td>8</td> <td>8</td> <td>–</td> <td> </td> <td>  </td></tr> <tr> <th>EV5 </th> <td><a href="/wiki/Alpha_21164" title="Alpha 21164">21164</a></td> <td>1995</td> <td>266–500</td> <td>0.5</td> <td>9.3</td> <td>299</td> <td>296</td> <td>56</td> <td>3.3/2.5</td> <td>8</td> <td>8</td> <td>96 KB</td> <td>Up to 64 MB</td> <td>R </td></tr> <tr> <th>EV56 </th> <td>21164A</td> <td>1996</td> <td>366–666<sup id="cite_ref-facts_and_comments_1-1" class="reference"><a href="#cite_note-facts_and_comments-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td> <td>0.35</td> <td>9.66<sup id="cite_ref-facts_and_comments_1-2" class="reference"><a href="#cite_note-facts_and_comments-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td> <td>209</td> <td></td> <td>31–55<sup id="cite_ref-facts_and_comments_1-3" class="reference"><a href="#cite_note-facts_and_comments-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td> <td>3.3/2.5<sup id="cite_ref-facts_and_comments_1-4" class="reference"><a href="#cite_note-facts_and_comments-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td> <td>8</td> <td>8</td> <td>96 KB</td> <td>Up to 64 MB</td> <td>R,B </td></tr> <tr> <th>PCA56 </th> <td>21164PC</td> <td>1997</td> <td>400–533</td> <td>0.35</td> <td>3.5</td> <td>141</td> <td>264</td> <td>26–35</td> <td>3.3/2.5</td> <td>8</td> <td>16</td> <td>–</td> <td>512 KB–4 MB</td> <td>R,B,M </td></tr> <tr> <th>PCA57 </th> <td>21164PC</td> <td> </td> <td>600–666</td> <td>0.28</td> <td>5.7</td> <td>101</td> <td>283</td> <td>18–23</td> <td>2.5/2.0</td> <td>16</td> <td>32<sup id="cite_ref-facts_and_comments_1-5" class="reference"><a href="#cite_note-facts_and_comments-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </td> <td>–</td> <td>512 KB–4 MB</td> <td>R,B,M </td></tr> <tr> <th>EV6 </th> <td><a href="/wiki/Alpha_21264" title="Alpha 21264">21264</a></td> <td>1998</td> <td>450–600</td> <td>0.35</td> <td>15.2</td> <td>314</td> <td>389</td> <td>73</td> <td>2.0</td> <td>64</td> <td>64</td> <td>–</td> <td>2–8 MB</td> <td>R,B,M,F </td></tr> <tr> <th>EV67 </th> <td>21264A</td> <td>1999</td> <td>600–750</td> <td>0.25</td> <td>15.2</td> <td>210</td> <td>389</td> <td> </td> <td>2.0</td> <td>64</td> <td>64</td> <td>–</td> <td>2–8 MB</td> <td>R,B,M,F,C </td></tr> <tr> <th>EV68AL </th> <td>21264B</td> <td>2001</td> <td>800–833</td> <td>0.18</td> <td>15.2</td> <td>125</td> <td> </td> <td> </td> <td>1.7</td> <td>64</td> <td>64</td> <td>–</td> <td>2–8 MB</td> <td>R,B,M,F,C,T </td></tr> <tr> <th>EV68CB </th> <td>21264C</td> <td>2001</td> <td>1000–1250</td> <td>0.18</td> <td>15.2</td> <td>125</td> <td> </td> <td>65–75</td> <td>1.65</td> <td>64</td> <td>64</td> <td>–</td> <td>2–8 MB</td> <td>R,B,M,F,C,T </td></tr> <tr> <th>EV68CX </th> <td>21264D</td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td>1.65</td> <td>64</td> <td>64</td> <td>–</td> <td>2–8 MB</td> <td>R,B,M,F,C,T </td></tr> <tr> <th>EV7 </th> <td><a href="/wiki/Alpha_21364" title="Alpha 21364">21364</a></td> <td>2003</td> <td>1000–1150</td> <td>0.18</td> <td>130</td> <td>397</td> <td></td> <td>125</td> <td>1.5</td> <td>64</td> <td>64</td> <td>1.75 MB</td> <td>–</td> <td>R,B,M,F,C,T </td></tr> <tr> <th>EV7z </th> <td>21364</td> <td>2004</td> <td>1300</td> <td>0.18</td> <td>130</td> <td>397</td> <td></td> <td>125</td> <td>1.5</td> <td>64</td> <td>64</td> <td>1.75 MB</td> <td>–</td> <td>R,B,M,F,C,T </td></tr> <tr> <th colspan="16">Cancelled </th></tr> <tr> <th>EV78/EV79 </th> <td>21364A</td> <td>Slated for 2004</td> <td>1700</td> <td>0.13</td> <td>152</td> <td>300</td> <td></td> <td>120</td> <td>1.2</td> <td>64</td> <td>64</td> <td>1.75 MB</td> <td>–</td> <td>R,B,M,F,C,T </td></tr> <tr> <th>EV8 </th> <td><a href="/wiki/Alpha_21464" title="Alpha 21464">21464</a></td> <td>Slated for 2003</td> <td>1200–2000</td> <td>0.125</td> <td>250</td> <td>420</td> <td>1800</td> <td>??</td> <td>1.2</td> <td>64</td> <td>64</td> <td>3 MB</td> <td>–</td> <td>R,B,M,F,C,T </td></tr></tbody></table> <dl><dt>ISA extensions</dt> <dd></dd></dl> <ul><li><b>R</b> – Hardware support for rounding to infinity and negative infinity.<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup></li> <li><b>B</b> – BWX, the "Byte/Word Extension", adding instructions to allow 8- and 16-bit operations from memory and I/O</li> <li><b>M</b> – MVI, "multimedia" instructions</li> <li><b>F</b> – FIX, instructions to move data between integer and floating-point registers and for square root</li> <li><b>C</b> – CIX, instructions for counting and finding bits</li> <li><b>T</b> – support for prefetch with modify intent to improve the performance of the first attempt to acquire a lock</li></ul> <div class="mw-heading mw-heading2"><h2 id="Performance">Performance</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=23" title="Edit section: Performance"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>To illustrate the comparative performance of Alpha-based systems, some <a href="/wiki/Standard_Performance_Evaluation_Corporation" title="Standard Performance Evaluation Corporation">Standard Performance Evaluation Corporation</a> (SPEC) performance numbers (SPECint95, SPECfp95) are listed below. Note that the SPEC results claim to report the measured performance of a whole computer system (CPU, bus, memory, compiler optimizer), not just the CPU. Also note that the benchmark and scale changed from 1992 to 1995. However, the figures give a rough impression of the performance of the Alpha architecture (64-bit), compared with the contemporary HP (64-bit) and Intel-based offerings (32-bit). Perhaps the most obvious trend is that while Intel could always get reasonably close to Alpha in integer performance, in floating-point performance the difference was considerable. On the other side, HP (<a href="/wiki/PA-RISC" title="PA-RISC">PA-RISC</a>) is also reasonably close to Alpha, but these CPUs are running at significantly lower clock rates (MHz). The tables lack two important values: the power consumption and the price of a CPU. </p> <style data-mw-deduplicate="TemplateStyles:r1216972533">.mw-parser-output .col-begin{border-collapse:collapse;padding:0;color:inherit;width:100%;border:0;margin:0}.mw-parser-output .col-begin-small{font-size:90%}.mw-parser-output .col-break{vertical-align:top;text-align:left}.mw-parser-output .col-break-2{width:50%}.mw-parser-output .col-break-3{width:33.3%}.mw-parser-output .col-break-4{width:25%}.mw-parser-output .col-break-5{width:20%}@media(max-width:720px){.mw-parser-output .col-begin,.mw-parser-output .col-begin>tbody,.mw-parser-output .col-begin>tbody>tr,.mw-parser-output .col-begin>tbody>tr>td{display:block!important;width:100%!important}.mw-parser-output .col-break{padding-left:0!important}}</style><div> <table class="col-begin" role="presentation"> <tbody><tr> <td class="col-break col-break-2"> <table class="wikitable" style="text-align:center; font-size:98%"> <tbody><tr> <th width="150">System </th> <th width="80">CPU </th> <th width="30">MHz </th> <th width="40">integer </th> <th width="50">floating point </th></tr> </tbody><caption>SPEC benchmark 1995 performance comparison (using <i>SPECint95</i> and <i>SPECfp95</i> results <a rel="nofollow" class="external autonumber" href="http://www.spec.org/cpu95/results/">[1]</a>) </caption> <tbody><tr> <th>AlphaServer 8400 5/350 </th> <td>21164 (EV5)</td> <td>350</td> <td>10.1</td> <td>14.2 </td></tr> <tr> <th>Intel Alder System (200 MHz, 256 KB L2) </th> <td><a href="/wiki/Pentium_Pro" title="Pentium Pro">Pentium Pro</a></td> <td>200</td> <td>8.9</td> <td>6.75 </td></tr> <tr> <th><a href="/wiki/HP_9000" title="HP 9000">HP 9000</a> C160 </th> <td><a href="/wiki/PA-8000" title="PA-8000">PA-8000</a></td> <td>160</td> <td>10.4</td> <td>16.3 </td></tr> </tbody></table> </td> <td class="col-break col-break-2"> <table class="wikitable" style="text-align:center; font-size:98%"> <tbody><tr> <th width="150">System </th> <th width="80">CPU </th> <th width="30">MHz </th> <th width="40">integer </th> <th width="50">floating point </th></tr> </tbody><caption>2000 performance comparison (using <i><a href="/wiki/SPECint" title="SPECint">SPECint</a>95</i> and <i>SPECfp95</i> results) </caption> <tbody><tr> <th>AlphaServer ES40 6/833 </th> <td>21264 (EV6)</td> <td>833</td> <td>50.0</td> <td>100.0 </td></tr> <tr> <th>Intel VC820 motherboard </th> <td><a href="/wiki/Pentium_III" title="Pentium III">Pentium III</a></td> <td>1000</td> <td>46.8</td> <td>31.9 </td></tr> <tr> <th>HP 9000 C3600 </th> <td><a href="/wiki/PA-8600" class="mw-redirect" title="PA-8600">PA-8600</a></td> <td>552</td> <td>42.1</td> <td>64.0 </td></tr> </tbody></table> <p>  </p> </td></tr></tbody></table></div> <div class="mw-heading mw-heading2"><h2 id="Alpha-based_systems">Alpha-based systems</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=24" title="Edit section: Alpha-based systems"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first generation of DEC Alpha-based systems comprise the <a href="/wiki/DEC_3000_AXP" title="DEC 3000 AXP">DEC 3000 AXP</a> series workstations and low-end servers, <a href="/wiki/DEC_4000_AXP" title="DEC 4000 AXP">DEC 4000 AXP</a> series mid-range servers, and <a href="/wiki/DEC_7000/10000_AXP" class="mw-redirect" title="DEC 7000/10000 AXP">DEC 7000 AXP and 10000 AXP</a> series high-end servers. The DEC 3000 AXP systems use the same <a href="/wiki/TURBOchannel" title="TURBOchannel">TURBOchannel</a> bus as the prior <a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS</a>-based DECstation models, whereas the 4000 is based on <a href="/wiki/Futurebus" title="Futurebus">Futurebus</a>+ and the 7000/10000 share an architecture with corresponding <a href="/wiki/VAX" title="VAX">VAX</a> models. </p><p>DEC also produced a <a href="/wiki/Personal_computer" title="Personal computer">personal computer</a> (PC) configuration Alpha workstation with an <a href="/wiki/Extended_Industry_Standard_Architecture" title="Extended Industry Standard Architecture">Extended Industry Standard Architecture</a> (EISA) bus, the <a href="/wiki/DECpc_AXP_150" title="DECpc AXP 150">DECpc AXP 150</a> (codename <i>Jensen</i>, also named the DEC 2000 AXP). This is the first Alpha system to support <a href="/wiki/Windows_NT" title="Windows NT">Windows NT</a>. DEC later produced Alpha versions of their Celebris XL and <a href="/wiki/Digital_Personal_Workstation" title="Digital Personal Workstation">Digital Personal Workstation</a> PC lines, with 21164 processors. </p><p>Digital also produced <a href="/wiki/Single-board_computer" title="Single-board computer">single-board computers</a> based on the <a href="/wiki/VMEbus" title="VMEbus">VMEbus</a> for embedded and industrial use. The first generation includes the 21068-based AXPvme 64 and AXPvme 64LC, and the 21066-based AXPvme 160. These were introduced on March 1, 1994. Later models such as the AXPvme 100, AXPvme 166 and AXPvme 230 are based on the 21066A processor, while the Alpha VME 4/224 and Alpha VME 4/288 are based on the 21064A processor. The last models, the Alpha VME 5/352 and Alpha VME 5/480, are based on the 21164 processor. </p><p>The 21066 chip is used in the <a href="/wiki/DEC_Multia" title="DEC Multia">DEC Multia</a> VX40/41/42 compact workstation and the ALPHAbook 1 laptop from Tadpole Technology. </p><p>In 1994, DEC launched a new range of <a href="/wiki/AlphaStation" title="AlphaStation">AlphaStation</a> and <a href="/wiki/AlphaServer" title="AlphaServer">AlphaServer</a> systems. These use 21064 or 21164 processors and introduced the <a href="/wiki/Peripheral_Component_Interconnect" title="Peripheral Component Interconnect">PCI</a> bus, <a href="/wiki/VGA" class="mw-redirect" title="VGA">VGA</a>-compatible <a href="/wiki/Frame_buffer" class="mw-redirect" title="Frame buffer">frame buffers</a> and <a href="/wiki/PS/2_connector" class="mw-redirect" title="PS/2 connector">PS/2</a>-style keyboards and mice. The AlphaServer 8000 series supersedes the DEC 7000/10000 AXP and also employs XMI and FutureBus+ buses. </p><p>The AlphaStation XP1000 is the first workstation based on the 21264 processor. Later AlphaServer/Station models based on the 21264 are categorised into <i>DS</i> (departmental server), <i>ES</i> (enterprise server) or <i>GS</i> (global server) families. </p><p>The final 21364 chip is used in the AlphaServer ES47, ES80 and GS1280 models and the AlphaStation ES47. </p><p>A number of <a href="/wiki/Original_equipment_manufacturer" title="Original equipment manufacturer">OEM</a> <a href="/wiki/Motherboard" title="Motherboard">motherboards</a> were produced by DEC, such as the 21066 and 21068-based AXPpci 33 "NoName", which was part of a major push into the OEM market by the company,<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> the 21164-based AlphaPC 164 and AlphaPC 164LX, the 21164PC-based AlphaPC 164SX and AlphaPC 164RX and the 21264-based AlphaPC 264DP. Several third parties such as Samsung and API also produced OEM motherboards such as the API UP1000 and UP2000. </p><p>To assist third parties in developing hardware and software for the platform, DEC produced Evaluation Boards, such as the EB64+ and EB164 for the Alpha 21064A and 21164 microprocessors respectively. </p><p>The 21164 and 21264 processors were used by <a href="/wiki/NetApp" title="NetApp">NetApp</a> in various <a href="/wiki/Network-attached_storage" title="Network-attached storage">network-attached storage</a> systems, while the 21064 and 21164 processors were used by <a href="/wiki/Cray" title="Cray">Cray</a> in their <a href="/wiki/Cray_T3D" title="Cray T3D">T3D</a> and <a href="/wiki/Cray_T3E" title="Cray T3E">T3E</a> <a href="/wiki/Massively_parallel" title="Massively parallel">massively parallel</a> supercomputers. </p> <div class="mw-heading mw-heading3"><h3 id="Supercomputers">Supercomputers</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=25" title="Edit section: Supercomputers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The fastest supercomputer based on Alpha processors was the <a href="/wiki/ASCI_Q" class="mw-redirect" title="ASCI Q">ASCI Q</a> at Los Alamos National Laboratory. The machine was built as an HP AlphaServer SC45/GS Cluster. It had 4096 Alpha (21264 EV-68, 1.25 GHz) CPUs, and reached an R<sub>max</sub> of 7.727 <a href="/wiki/TFLOPS" class="mw-redirect" title="TFLOPS">TFLOPS</a>.<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=26" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-lower-alpha"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-35"><span class="mw-cite-backlink"><b><a href="#cite_ref-35">^</a></b></span> <span class="reference-text">In the context of data transfer, 1 GB is used to mean 1 billion bytes</span> </li> <li id="cite_note-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-39">^</a></b></span> <span class="reference-text">In the context of cache memory, 1 KB = 1024 <a href="/wiki/Byte" title="Byte">bytes</a>; 1 MB = 1024 KB</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=27" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626" /><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-facts_and_comments-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-facts_and_comments_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-facts_and_comments_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-facts_and_comments_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-facts_and_comments_1-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-facts_and_comments_1-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-facts_and_comments_1-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFPaul_V._Bolotoff2007" class="citation web cs1">Paul V. 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Interviewed by Gardner Hendrie. Computer History Museum<span class="reference-accessdate">. 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April 1993. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210207063545/https://dspace.mit.edu/bitstream/handle/1721.1/48380/managingtechnolo00katz.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2021-02-07<span class="reference-accessdate">. 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Digital Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-4831-8403-6" title="Special:BookSources/978-1-4831-8403-6"><bdi>978-1-4831-8403-6</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180920122621/https://www.elsevier.com/books/alpha-axp-architecture-reference-manual/sites/978-1-4831-8403-6">Archived</a> from the original on 2018-09-20<span class="reference-accessdate">. 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Retrieved <span class="nowrap">2018-09-20</span></span>. <q>The first processors of the Alpha family were designated the DECchip 21064 series (the "21" signifying 21st century)</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=cpu-collection.de+%E2%80%93+DEC+Alpha+AXP&rft_id=http%3A%2F%2Fwww.cpu-collection.de%2F%3Fl0%3Dco%26l1%3DDEC%26l2%3DAlpha%2BAXP&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-pickle-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-pickle_19-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFBill_HamburgenJeff_MogulBrian_ReidAlan_Eustace1989" class="citation journal cs1">Bill Hamburgen; Jeff Mogul; <a href="/wiki/Brian_Reid_(computer_scientist)" title="Brian Reid (computer scientist)">Brian Reid</a>; <a href="/wiki/Alan_Eustace" title="Alan Eustace">Alan Eustace</a>; Richard Swan; Mary Jo Doherty; Joel Bartlett (1989). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080512033558/http://www.hpl.hp.com/techreports/Compaq-DEC/WRL-TN-13.html">"WRL Technical Note TN-13: Characterization of Organic Illumination Systems"</a>. 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Vol. 43, no. 2168. pp. 1, 60. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1061-6624">1061-6624</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Electronic+News&rft.atitle=DEC%2C+Cyrix+sue+Intel&rft.volume=43&rft.issue=2168&rft.pages=1%2C+60&rft.date=1997-05-19&rft.issn=1061-6624&rft.aulast=Bradley&rft.aufirst=Gale&rft.au=DeTar%2C+Jim&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fsim_electronic-news_1997-05-19_43_2168%2Fmode%2F1up&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFBaum2018" class="citation interview cs1">Baum, Allan (July 18, 2018). <a rel="nofollow" class="external text" href="https://archive.computerhistory.org/resources/access/text/2018/06/102717165-05-01-acc.pdf">"Oral History of Allen Baum"</a> <span class="cs1-format">(PDF)</span> (Interview). Interviewed by David Brock. p. 60. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210207063355/https://archive.computerhistory.org/resources/access/text/2018/06/102717165-05-01-acc.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2021-02-07.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Oral+History+of+Allen+Baum&rft.pages=60&rft.date=2018-07-18&rft.aulast=Baum&rft.aufirst=Allan&rft_id=https%3A%2F%2Farchive.computerhistory.org%2Fresources%2Faccess%2Ftext%2F2018%2F06%2F102717165-05-01-acc.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFCharles_P._ThackerDavid_G._ConroyLawrence_C._Stewart1992" class="citation journal cs1">Charles P. 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In Danielle C. Martin (ed.). <i>Proceedings: 29th Annual International Symposium on Computer Architecture (ISCA '02)</i>. <a rel="nofollow" class="external text" href="http://systems.cs.colorado.edu/ISCA2002">29th Annual International Symposium on Computer Architecture (ISCA '02)</a>. Joe Daigle/Studio Productions. Los Alamitos, Calif: IEEE Computer Society. pp. <span class="nowrap">281–</span>292. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FISCA.2002.1003586">10.1109/ISCA.2002.1003586</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-7695-1605-X" title="Special:BookSources/0-7695-1605-X"><bdi>0-7695-1605-X</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20071004172421/http://systems.cs.colorado.edu/ISCA2002/">Archived</a> from the original on 2007-10-04<span class="reference-accessdate">. Retrieved <span class="nowrap">2007-10-04</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Tarantula%3A+A+Vector+Extension+to+the+Alpha+Architecture&rft.btitle=Proceedings%3A+29th+Annual+International+Symposium+on+Computer+Architecture+%28ISCA+%2702%29&rft.place=Los+Alamitos%2C+Calif&rft.pages=%3Cspan+class%3D%22nowrap%22%3E281-%3C%2Fspan%3E292&rft.pub=IEEE+Computer+Society&rft.date=2002&rft_id=info%3Adoi%2F10.1109%2FISCA.2002.1003586&rft.isbn=0-7695-1605-X&rft.au=Roger+Espasa&rft.au=Federico+Ardanaz&rft.au=Julio+Gago&rft.au=Roger+Gramunt&rft.au=Isaac+Hernandez&rft.au=Toni+Juan&rft.au=Joel+Emer&rft.au=Stephen+Felix&rft.au=Geoff+Lowney&rft.au=Matthew+Mattina&rft.au=Andre+Seznec&rft_id=http%3A%2F%2Fsystems.cs.colorado.edu%2FISCA2002%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://groups.google.com/d/topic/comp.os.vms/8ptFdR3KYxg">"The VAX Vacuum"</a>. <q>... legally, if DEC had used VAX in the U.S. before that ..... "reasonable person" has no difficulty distinguishing between the two uses</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+VAX+Vacuum&rft_id=https%3A%2F%2Fgroups.google.com%2Fd%2Ftopic%2Fcomp.os.vms%2F8ptFdR3KYxg&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFChad_Page1996" class="citation mailinglist cs1">Chad Page (30 April 1996). <a rel="nofollow" class="external text" href="https://lkml.org/lkml/1996/5/1/47">"The meaning of AXP (was Re: ALPHA ambiguity)"</a>. <i>Linux kernel mailing list</i> (Mailing list)<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-08-29</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+meaning+of+AXP+%28was+Re%3A+ALPHA+ambiguity%29&rft.date=1996-04-30&rft.au=Chad+Page&rft_id=https%3A%2F%2Flkml.org%2Flkml%2F1996%2F5%2F1%2F47&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://devblogs.microsoft.com/oldnewthing/20170816-00/?p=96825">"The Alpha AXP, part 8: Memory access, storing bytes and words and unaligned data"</a>. August 16, 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">July 18,</span> 2022</span>. <q>Dealing with unaligned memory on the Alpha AXP is very annoying</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+Alpha+AXP%2C+part+8%3A+Memory+access%2C+storing+bytes+and+words+and+unaligned+data&rft.date=2017-08-16&rft_id=https%3A%2F%2Fdevblogs.microsoft.com%2Foldnewthing%2F20170816-00%2F%3Fp%3D96825&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-29">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.star.bnl.gov/public/daq/HARDWARE/21264_data_sheet.pdf">"Alpha 21264 Microprocessor Data Sheet"</a> <span class="cs1-format">(PDF)</span>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170830002919/http://www.star.bnl.gov/public/daq/HARDWARE/21264_data_sheet.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2017-08-30<span class="reference-accessdate">. Retrieved <span class="nowrap">2018-09-20</span></span>. <q>The instructions that comprise the BWX extension are ...</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Alpha+21264+Microprocessor+Data+Sheet&rft_id=https%3A%2F%2Fwww.star.bnl.gov%2Fpublic%2Fdaq%2FHARDWARE%2F21264_data_sheet.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://eas.uccs.edu/~cwang/ECE4480_sp_16/ch2(3rdEdition).PPT">"MIPS Instructions"</a>. <q>DEC Alpha ... , no integer condition code.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=MIPS+Instructions&rft_id=http%3A%2F%2Feas.uccs.edu%2F~cwang%2FECE4480_sp_16%2Fch2%283rdEdition%29.PPT&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span><sup class="noprint Inline-Template"><span style="white-space: nowrap;">[<i><a href="/wiki/Wikipedia:Link_rot" title="Wikipedia:Link rot"><span title=" Dead link tagged February 2022">permanent dead link</span></a></i><span style="visibility:hidden; color:transparent; padding-left:2px">‍</span>]</span></sup></span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation magazine cs1">"Alpha Bits – Migrating To The Future". <i>DEC Professional</i>. August 1992. p. 62. <q>H floating datatypes are unavailable on Alpha</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=DEC+Professional&rft.atitle=Alpha+Bits+%E2%80%93+Migrating+To+The+Future&rft.pages=62&rft.date=1992-08&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-32">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www0.mi.infn.it/~calcolo/OpenVMS/ssb71/6459/6459p002.htm">"Migrating an Application from OpenVMS VAX to OpenVMS Alpha"</a>. 2.5.2 Data Types.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Migrating+an+Application+from+OpenVMS+VAX+to+OpenVMS+Alpha&rft.pages=2.5.2+Data+Types&rft_id=https%3A%2F%2Fwww0.mi.infn.it%2F~calcolo%2FOpenVMS%2Fssb71%2F6459%2F6459p002.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-33">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFGronowskiBowhillDonchinBlake-Campos1996" class="citation journal cs1">Gronowski, P. E.; Bowhill, W. J.; Donchin, D. R.; Blake-Campos, R. P.; Carlson, D. A.; Equi, E. R.; Loughlin, B. J.; Mehta, S.; Mueller, R. O.; Olesin, A.; Noorlag, D. J. W.; Preston, R. P. (1996). 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"Digital, MIPS Add Multimedia Extensions". <i><a href="/wiki/Microprocessor_Report" title="Microprocessor Report">Microprocessor Report</a></i>.</span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFLuiz_André_BarrosoKourosh_GharachorlooRobert_McNamaraAndreas_Nowatzyk2000" class="citation conference cs1">Luiz André Barroso; Kourosh Gharachorloo; Robert McNamara; Andreas Nowatzyk; Shaz Qadeer; Barton Sano; Scott Smith; Robert Stets; Ben Verghese (2000). <i>Piranha: A Scalable Architecture Based on Single-Chip Multiprocessing</i>. 27th Annual International Symposium on Computer Architecture. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F339647.339696">10.1145/339647.339696</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Piranha%3A+A+Scalable+Architecture+Based+on+Single-Chip+Multiprocessing&rft.date=2000&rft_id=info%3Adoi%2F10.1145%2F339647.339696&rft.au=Luiz+Andr%C3%A9+Barroso&rft.au=Kourosh+Gharachorloo&rft.au=Robert+McNamara&rft.au=Andreas+Nowatzyk&rft.au=Shaz+Qadeer&rft.au=Barton+Sano&rft.au=Scott+Smith&rft.au=Robert+Stets&rft.au=Ben+Verghese&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFHung-Sheng_Tsao2011" class="citation web cs1">Hung-Sheng Tsao (2011-10-29). <a rel="nofollow" class="external text" href="http://laotsao.wordpress.com/2011/10/29/sw1600-and-alpha-21164/">"SW1600 and Alpha 21164"</a>. <i>LaoTsao's Weblog</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2011-10-29</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=LaoTsao%27s+Weblog&rft.atitle=SW1600+and+Alpha+21164&rft.date=2011-10-29&rft.au=Hung-Sheng+Tsao&rft_id=http%3A%2F%2Flaotsao.wordpress.com%2F2011%2F10%2F29%2Fsw1600-and-alpha-21164%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-dongarra2016-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-dongarra2016_38-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFDongarra2016" class="citation web cs1">Dongarra, Jack (2016-06-20). <a rel="nofollow" class="external text" href="http://www.netlib.org/utk/people/JackDongarra/PAPERS/sunway-report-2016.pdf">"Report on the Sunway TaihuLight System"</a> <span class="cs1-format">(PDF)</span>. <i>www.netlib.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2016-06-20</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.netlib.org&rft.atitle=Report+on+the+Sunway+TaihuLight+System&rft.date=2016-06-20&rft.aulast=Dongarra&rft.aufirst=Jack&rft_id=http%3A%2F%2Fwww.netlib.org%2Futk%2Fpeople%2FJackDongarra%2FPAPERS%2Fsunway-report-2016.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFDavid_Mosberger" class="citation web cs1">David Mosberger. <a rel="nofollow" class="external text" href="http://www.mostang.com/~davidm/papers/expo97/paper/doc003.html">"Overview of Alpha Family"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20090120232139/http://mostang.com/~davidm/papers/expo97/paper/doc003.html">Archived</a> from the original on January 20, 2009<span class="reference-accessdate">. Retrieved <span class="nowrap">Dec 9,</span> 2009</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Overview+of+Alpha+Family&rft.au=David+Mosberger&rft_id=http%3A%2F%2Fwww.mostang.com%2F~davidm%2Fpapers%2Fexpo97%2Fpaper%2Fdoc003.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> <li id="cite_note-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-41">^</a></b></span> <span class="reference-text">Reinhardt Krause. "DEC launching Alpha board push". Electronic News, April 4, 1994.</span> </li> <li id="cite_note-42"><span class="mw-cite-backlink"><b><a href="#cite_ref-42">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFLos_Alamos_National_Laboratories2002" class="citation web cs1">Los Alamos National Laboratories (2002). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110112020420/http://www.sandia.gov/supercomp/sc2002/flyers/ASCI_Q_rev.pdf">"The ASCI Q System: 30 TeraOPS Capability at Los Alamos National Laboratory"</a> <span class="cs1-format">(PDF)</span>. Archived from <a rel="nofollow" class="external text" href="http://www.sandia.gov/supercomp/sc2002/flyers/ASCI_Q_rev.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2011-01-12<span class="reference-accessdate">. Retrieved <span class="nowrap">2010-06-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+ASCI+Q+System%3A+30+TeraOPS+Capability+at+Los+Alamos+National+Laboratory&rft.date=2002&rft.au=Los+Alamos+National+Laboratories&rft_id=http%3A%2F%2Fwww.sandia.gov%2Fsupercomp%2Fsc2002%2Fflyers%2FASCI_Q_rev.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADEC+Alpha" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=DEC_Alpha&action=edit&section=28" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.o3one.org/hwdocs/alpha/alphaahb.pdf">The Alpha Architecture Handbook, Version 4</a></li> <li><a rel="nofollow" class="external text" href="https://www.cs.cmu.edu/afs/cs/academic/class/15213-f98/doc/alpha-ref.pdf">The Alpha Architecture Handbook, Version 3</a></li> <li><a rel="nofollow" class="external text" href="https://www.hpl.hp.com/hpjournal/dtj/vol4num4/toc.htm">Digital Technical Journal, Volume 4, Number 4, Special Issue 1992 Alpha AXP Architecture and Systems</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230123052748/https://www.hpl.hp.com/hpjournal/dtj/vol4num4/toc.htm">Archived</a> 2023-01-23 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> This issue contains several articles from Alpha's Architects</li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20080404230535/http://h18002.www1.hp.com/alphaserver/technology/chip-docs.html">Archived technical documentation library</a> This link features the hardware reference manuals and datasheets for Alpha microprocessors, chipsets and OEM motherboards. Includes the Alpha Architecture Handbook and various programming manuals.</li> <li><a rel="nofollow" class="external text" href="http://queue.acm.org/detail.cfm?id=957732">A Conversation with Dan Dobberpuhl (October 1, 2003)</a></li> <li><a rel="nofollow" class="external text" href="https://www.cs.auckland.ac.nz/courses/compsci210s2c/resources/AlphaArch.pdf">Dr. Bruce Hutton's lecture notes on Computer Architecture</a></li></ul> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Digital_Equipment_Corporation805" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" 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class="navbox-group" style="width:1%">Key people</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ken_Olsen" title="Ken Olsen">Ken Olsen</a> (founder and CEO, 1957–1992)</li> <li><a href="/wiki/Harlan_Anderson" title="Harlan Anderson">Harlan Anderson</a> (co-founder)</li> <li><a href="/wiki/Gordon_Bell" title="Gordon Bell">Gordon Bell</a> (VP of engineering)</li> <li><a href="/wiki/Robert_Palmer_(computer_businessman)" title="Robert Palmer (computer businessman)">Robert Palmer</a> (CEO, 1992–1998)</li></ul> </div></td><td class="noviewer navbox-image" rowspan="9" style="width:1px;padding:0 0 0 2px"><div><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Digital_Equipment_Corporation_1993_logo.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Digital_Equipment_Corporation_1993_logo.svg/120px-Digital_Equipment_Corporation_1993_logo.svg.png" decoding="async" width="110" height="33" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Digital_Equipment_Corporation_1993_logo.svg/250px-Digital_Equipment_Corporation_1993_logo.svg.png 1.5x" data-file-width="3124" data-file-height="938" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Instruction_set_architecture" title="Instruction set architecture">Instruction set<br />architectures</a>,<br /><a href="/wiki/Processor_(computing)" title="Processor (computing)">processors</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/PDP-11_architecture" title="PDP-11 architecture">PDP-11</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>LSI-11</li> <li>F-11</li> <li><a href="/wiki/DEC_T-11" title="DEC T-11">T-11</a></li> <li><a href="/wiki/DEC_J-11" title="DEC J-11">J-11</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/VAX" title="VAX">VAX</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DEC_V-11" title="DEC V-11">V-11</a></li> <li><a href="/wiki/MicroVAX_78032" title="MicroVAX 78032">MicroVAX 78032</a></li> <li><a href="/wiki/CVAX" title="CVAX">CVAX</a> <ul><li><a href="/wiki/CVAX#SOC" title="CVAX">SOC</a></li></ul></li> <li><a href="/wiki/Rigel_(microprocessor)" title="Rigel (microprocessor)">Rigel</a> <ul><li><a href="/wiki/Rigel_(microprocessor)#Mariah" title="Rigel (microprocessor)">Mariah</a></li></ul></li> <li><a href="/wiki/NVAX" title="NVAX">NVAX</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a class="mw-selflink selflink">Alpha</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alpha_21064" title="Alpha 21064">Alpha 21064</a> <ul><li><a href="/wiki/Alpha_21064#Alpha_21066" title="Alpha 21064">21066</a></li> <li><a href="/wiki/Alpha_21064#Alpha_21068" title="Alpha 21064">21068</a></li></ul></li> <li><a href="/wiki/Alpha_21164" title="Alpha 21164">Alpha 21164</a> (<a href="/wiki/Alpha_21164#Alpha_21164PC_(PCA56)" title="Alpha 21164">21164PC</a>)</li> <li><a href="/wiki/Alpha_21264" title="Alpha 21264">Alpha 21264</a></li> <li><a href="/wiki/Alpha_21364" title="Alpha 21364">Alpha 21364</a></li> <li><a href="/wiki/Alpha_21464" title="Alpha 21464">Alpha 21464</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DEC_PRISM" title="DEC PRISM">MicroPRISM</a></li> <li><a href="/wiki/StrongARM" title="StrongARM">StrongARM</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Computer_terminal" title="Computer terminal">Computer<br />terminals</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/VT05" title="VT05">VT05</a> (1970)</li> <li><a href="/wiki/DEC_GT40" title="DEC GT40">GT40</a> (1972)</li> <li><a href="/wiki/VT52" title="VT52">VT50/VT52</a> (1975)</li> <li><a href="/wiki/VT55" class="mw-redirect" title="VT55">VT55</a></li> <li><a href="/wiki/VT62" class="mw-redirect" title="VT62">VT62</a></li> <li><a href="/wiki/VT100" title="VT100">VT100</a> (1978)</li> <li><a href="/wiki/VT101" class="mw-redirect" title="VT101">VT101</a></li> <li><a href="/wiki/VT102" class="mw-redirect" title="VT102">VT102</a></li> <li><a href="/wiki/VT103" class="mw-redirect" title="VT103">VT103</a></li> <li><a href="/wiki/VT105" class="mw-redirect" title="VT105">VT105</a></li> <li><a href="/wiki/VT131" class="mw-redirect" title="VT131">VT131</a></li> <li><a href="/wiki/VT180" title="VT180">VT180</a></li> <li><a href="/wiki/VT220" title="VT220">VT220</a> (1983)</li> <li><a href="/wiki/VT240" class="mw-redirect" title="VT240">VT240</a></li> <li><a href="/wiki/VT241" class="mw-redirect" title="VT241">VT241</a></li> <li><a href="/wiki/VT320" title="VT320">VT320</a> (1987)</li> <li><a href="/wiki/VT330" class="mw-redirect" title="VT330">VT330</a></li> <li><a href="/wiki/VT340" class="mw-redirect" title="VT340">VT340</a></li> <li><a href="/wiki/VT420" title="VT420">VT420</a> (1990)</li> <li><a href="/wiki/VT1000" title="VT1000">VT1000</a> (1990)</li> <li><a href="/wiki/VT510" class="mw-redirect" title="VT510">VT510</a> (1993)</li> <li><a href="/wiki/VT520" title="VT520">VT520</a> (1994)</li> <li><a href="/wiki/VT525" class="mw-redirect" title="VT525">VT525</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Operating_system" title="Operating system">Operating<br />systems</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PDP-7#Software" title="PDP-7">DECsys</a></li> <li><a href="/wiki/4K_Disk_Monitor_System" class="mw-redirect" title="4K Disk Monitor System">4K DMS</a></li> <li><a href="/wiki/Commercial_Operating_System" title="Commercial Operating System">COS</a></li> <li><a href="/wiki/TOPS-10" title="TOPS-10">TOPS-10</a></li> <li><a href="/wiki/RSX-15" class="mw-redirect" title="RSX-15">RSX-15</a></li> <li><a href="/wiki/TSS/8" title="TSS/8">TSS/8</a></li> <li><a href="/wiki/OS/8" title="OS/8">OS/8</a></li> <li><a href="/wiki/DEC_BATCH-11/DOS-11" title="DEC BATCH-11/DOS-11">DOS-11</a></li> <li><a href="/wiki/RT-11" title="RT-11">RT-11</a></li> <li><a href="/wiki/RSTS/E" title="RSTS/E">RSTS/E</a></li> <li><a href="/wiki/RSX-11" title="RSX-11">RSX-11</a> <ul><li><a href="/wiki/Interactive_Application_System" title="Interactive Application System">IAS</a></li></ul></li> <li><a href="/wiki/MUMPS#1970s" title="MUMPS">DSM-11</a></li> <li><a href="/wiki/TOPS-20" title="TOPS-20">TOPS-20</a></li> <li><a href="/wiki/OpenVMS" title="OpenVMS">VAX/VMS</a></li> <li><a href="/wiki/VAXELN" title="VAXELN">VAXELN</a></li> <li><a href="/wiki/Ultrix" title="Ultrix">Ultrix</a></li> <li><a href="/wiki/DEC_MICA" title="DEC MICA">MICA</a></li> <li><a href="/wiki/Digital_UNIX" class="mw-redirect" title="Digital UNIX">Digital UNIX</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Programming_language" title="Programming language">Programming<br />languages</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/BASIC-8" title="BASIC-8">BASIC-8</a></li> <li><a href="/wiki/DIBOL" title="DIBOL">DIBOL</a></li> <li><a href="/wiki/FOCAL_(programming_language)" title="FOCAL (programming language)">FOCAL</a></li> <li><a href="/wiki/MACRO-10" title="MACRO-10">MACRO-10</a></li> <li><a href="/wiki/MACRO-11" title="MACRO-11">MACRO-11</a></li> <li><a href="/wiki/MUMPS" title="MUMPS">MUMPS</a></li> <li><a href="/wiki/VAX_MACRO" title="VAX MACRO">VAX MACRO</a></li> <li><a href="/wiki/DIGITAL_Command_Language" title="DIGITAL Command Language">DIGITAL Command Language</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Character_encoding" title="Character encoding">Character sets</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Multinational_Character_Set" title="Multinational Character Set">Code page 1100</a> (Multinational)</li> <li><a href="/wiki/Code_page_1287" title="Code page 1287">Code page 1287</a> (Greek)</li> <li><a href="/wiki/Code_page_1288" title="Code page 1288">Code page 1288</a> (Turkish)</li> <li><a href="/wiki/DEC_Hebrew" title="DEC Hebrew">Hebrew</a></li> <li><a href="/wiki/National_Replacement_Character_Set" title="National Replacement Character Set">National Replacement</a></li> <li><a href="/wiki/DEC_RADIX_50" title="DEC RADIX 50">RADIX 50</a></li> <li><a href="/wiki/DEC_Special_Graphics" title="DEC Special Graphics">Special Graphics</a></li> <li><a href="/wiki/DEC_Technical_Character_Set" title="DEC Technical Character Set">Technical</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Bus_(computing)" title="Bus (computing)">Bus standards</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Digital_Storage_Systems_Interconnect" title="Digital Storage Systems Interconnect">Digital Storage Systems Interconnect</a></li> <li><a href="/wiki/Massbus" title="Massbus">Massbus</a></li> <li><a href="/wiki/Q-Bus" title="Q-Bus">Q-Bus</a></li> <li><a href="/wiki/Standard_Disk_Interconnect" title="Standard Disk Interconnect">Standard Disk Interconnect</a></li> <li><a href="/wiki/Synchronous_Backplane_Interconnect" title="Synchronous Backplane Interconnect">Synchronous Backplane Interconnect</a></li> <li><a href="/wiki/TURBOchannel" title="TURBOchannel">TURBOchannel</a></li> <li><a href="/wiki/Unibus" title="Unibus">Unibus</a></li> <li><a href="/wiki/VAXBI_bus" title="VAXBI bus">VAXBI bus</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other <a href="/wiki/Computer_hardware" title="Computer hardware">hardware</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DECtalk" title="DECtalk">DECtalk</a></li> <li><a href="/wiki/DECtape" title="DECtape">DECtape</a></li> <li><a href="/wiki/DECwriter" title="DECwriter">DECwriter</a></li> <li><a href="/wiki/Digital_Linear_Tape" title="Digital Linear Tape">Digital Linear Tape</a></li> <li><a href="/wiki/Dynamically_Redefined_Character_Set" title="Dynamically Redefined Character Set">Dynamically Redefined Character Set</a></li> <li><a href="/wiki/Firefly_(cache_coherence_protocol)" title="Firefly (cache coherence protocol)">Firefly</a></li> <li><a href="/wiki/Flip-Chip_module" title="Flip-Chip module">Flip-Chip module</a></li> <li><a href="/wiki/Gold_key_(DEC)" title="Gold key (DEC)">Gold key</a></li> <li><a href="/wiki/LK201" title="LK201">LK201</a></li> <li><a href="/wiki/LK421" title="LK421">LK421</a></li> <li><a href="/wiki/Mass_Storage_Control_Protocol" title="Mass Storage Control Protocol">Mass Storage Control Protocol</a></li> <li><a href="/wiki/PALcode" title="PALcode">PALcode</a></li> <li><a href="/wiki/RA90" title="RA90">RA90</a></li> <li><a href="/wiki/RK05" title="RK05">RK05</a></li> <li><a href="/wiki/RL02" title="RL02">RL02</a></li> <li><a href="/wiki/Star_coupler" title="Star coupler">Star coupler</a></li> <li><a href="/wiki/System_Module" title="System Module">System Module</a></li> <li><a href="/wiki/TU81" title="TU81">TU81</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related topics</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AdvFS" title="AdvFS">AdvFS</a></li> <li><a href="/wiki/AltaVista" title="AltaVista">AltaVista</a></li> <li><a href="/wiki/Compaq" title="Compaq">Compaq</a></li> <li><i><a href="/wiki/CPU_Wars" title="CPU Wars">CPU Wars</a></i></li> <li><a href="/wiki/DECnet" title="DECnet">DECnet</a></li> <li><a href="/wiki/DECUS" title="DECUS">DECUS</a> <ul><li><a href="/wiki/HP-Interex" title="HP-Interex">HP-Interex</a></li></ul></li> <li><a href="/wiki/Digital_Federal_Credit_Union" title="Digital Federal Credit Union">Digital Federal Credit Union</a></li> <li><a href="/wiki/Dynamic_debugging_technique" title="Dynamic debugging technique">Dynamic debugging technique</a></li> <li><a href="/wiki/FX!32" title="FX!32">FX!32</a></li> <li><a href="/wiki/Local_Area_Transport" title="Local Area Transport">Local Area Transport</a></li> <li><a href="/wiki/Maintenance_Operations_Protocol" title="Maintenance Operations Protocol">Maintenance Operations Protocol</a></li> <li><a href="/wiki/On-line_Debugging_Tool" title="On-line Debugging Tool">On-line Debugging Tool</a></li> <li><a href="/wiki/PALcode" title="PALcode">PALcode</a></li> <li><a href="/wiki/Record_Management_Services" title="Record Management Services">Record Management Services</a></li> <li><a href="/wiki/ReGIS" title="ReGIS">ReGIS</a></li> <li>Sequence and Batch Language</li> <li><a href="/wiki/Sixel" title="Sixel">Sixel</a></li> <li><a href="/wiki/System_Reference_Manual" class="mw-redirect" title="System Reference Manual">System Reference Manual</a></li> <li><a href="/wiki/DEC_Systems_Research_Center" title="DEC Systems Research Center">Systems Research Center</a></li> <li><a href="/wiki/TD/SMP" title="TD/SMP">TD/SMP</a></li> <li><i><a href="/wiki/The_Ultimate_Entrepreneur" title="The Ultimate Entrepreneur">The Ultimate Entrepreneur</a></i></li> <li><a href="/wiki/VT640" title="VT640">VT640</a></li> <li><a href="/wiki/WPS-8" title="WPS-8">WPS-8</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="3"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Template"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/16px-Symbol_template_class_pink.svg.png" 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href="/wiki/Programmed_Data_Processor" title="Programmed Data Processor">PDP</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0;background:transparent;color:inherit;"><div style="padding:0px"><table class="navbox-columns-table" style="border-spacing: 0px; text-align:left;width:100%;"><tbody><tr style="vertical-align:top"><td class="navbox-list" style="padding:0px;vertical-align:top;width:50%;"><div> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/18-bit_computing" title="18-bit computing">18-bit</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PDP-1" title="PDP-1">PDP-1</a></li> <li><a href="/wiki/PDP-4" title="PDP-4">PDP-4</a></li> <li><a href="/wiki/PDP-7" title="PDP-7">PDP-7</a></li> <li><a href="/wiki/PDP-9" title="PDP-9">PDP-9</a></li> <li><a href="/wiki/PDP-15" title="PDP-15">PDP-15</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/12-bit_computing" title="12-bit computing">12-bit</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/LINC" title="LINC">LINC</a> <ul><li><a href="/wiki/LINC-8" title="LINC-8">LINC-8</a></li></ul></li> <li><a href="/wiki/PDP-5" title="PDP-5">PDP-5</a></li> <li><a href="/wiki/PDP-8" title="PDP-8">PDP-8</a> <ul><li><a href="/wiki/PDP-8/e" title="PDP-8/e">PDP-8/e</a></li></ul></li> <li><a href="/wiki/PDP-12" title="PDP-12">PDP-12</a></li> <li><a href="/wiki/DECmate" title="DECmate">DECmate</a></li> <li><a href="/wiki/PDP-14" title="PDP-14">PDP-14</a></li></ul> </div></td></tr></tbody></table><div> </div></td><td class="navbox-list" style="border-left:2px solid #fdfdfd;padding:0px;vertical-align:top;width:50%;"><div> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/36-bit_computing" title="36-bit computing">36-bit</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PDP-6" title="PDP-6">PDP-6</a></li> <li><a href="/wiki/PDP-10" title="PDP-10">PDP-10</a></li> <li><a href="/wiki/DECSYSTEM-20" title="DECSYSTEM-20">DECSYSTEM-20</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/16-bit_computing" title="16-bit computing">16-bit</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PDP-11" title="PDP-11">PDP-11</a></li> <li><a href="/wiki/DEC_Professional" title="DEC Professional">DEC Professional</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/VAX" title="VAX">VAX</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/VAX-11" title="VAX-11">VAX-11</a></li> <li><a href="/wiki/MicroVAX" title="MicroVAX">MicroVAX</a></li> <li><a href="/wiki/VAX_8000" title="VAX 8000">VAX 8000</a></li> <li><a href="/wiki/VAXstation" title="VAXstation">VAXstation</a></li> <li><a href="/wiki/DEC_Firefly" title="DEC Firefly">Firefly</a></li> <li><a href="/wiki/VAXserver" title="VAXserver">VAXserver</a></li> <li><a href="/wiki/VAX_6000" title="VAX 6000">VAX 6000</a></li> <li><a href="/wiki/VAX_4000" title="VAX 4000">VAX 4000</a></li> <li><a href="/wiki/VAX_9000" title="VAX 9000">VAX 9000</a></li> <li><a href="/wiki/VAXft" title="VAXft">VAXft</a></li> <li><a href="/wiki/VAX_7000_and_VAX_10000" title="VAX 7000 and VAX 10000">VAX 7000 and VAX 10000</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/X86" title="X86">x86</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Rainbow_100" title="Rainbow 100">Rainbow 100</a></li> <li><a href="/wiki/VAXmate" title="VAXmate">VAXmate</a></li> <li><a href="/wiki/DECpc" title="DECpc">DECpc</a></li> <li><a href="/wiki/DECstation#PC" title="DECstation">DECstation</a></li> <li><a href="/wiki/DEC_Multia" title="DEC Multia">Multia</a></li> <li><a href="/wiki/Digital_Personal_Workstation" title="Digital Personal Workstation">Digital Personal Workstation</a></li> <li><a href="/wiki/Digital_HiNote" title="Digital HiNote">HiNote</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DECstation#MIPS" title="DECstation">DECstation</a></li> <li><a href="/wiki/DECsystem" title="DECsystem">DECsystem servers</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a class="mw-selflink selflink">Alpha</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DEC_3000_AXP" title="DEC 3000 AXP">DEC 3000 AXP</a></li> <li><a href="/wiki/DEC_4000_AXP" title="DEC 4000 AXP">DEC 4000 AXP</a></li> <li><a href="/wiki/DEC_7000_AXP_and_DEC_10000_AXP" title="DEC 7000 AXP and DEC 10000 AXP">DEC 7000 AXP and DEC 10000 AXP</a></li> <li><a href="/wiki/DECpc_AXP_150" title="DECpc AXP 150">DECpc AXP 150</a></li> <li><a href="/wiki/DECpc_AXP_150#DEC_2000_AXP" title="DECpc AXP 150">DEC 2000 AXP</a></li> <li><a href="/wiki/DEC_Multia" title="DEC Multia">Multia</a></li> <li><a href="/wiki/AlphaServer" title="AlphaServer">AlphaServer</a></li> <li><a href="/wiki/AlphaStation" title="AlphaStation">AlphaStation</a></li> <li><a href="/wiki/Digital_Personal_Workstation" title="Digital Personal Workstation">Digital Personal Workstation</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">See also</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_Professional_Workstation" title="Compaq Professional Workstation">Compaq Professional Workstation 1000 XP</a></li> <li><a href="/wiki/Itsy_Pocket_Computer" title="Itsy Pocket Computer">Itsy Pocket Computer</a></li> <li><a href="/wiki/Jupiter_project" title="Jupiter project">Jupiter project</a></li> <li><a href="/wiki/List_of_VAX_computers" title="List of VAX computers">List of VAX computers</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:DEC_computers" title="Category:DEC computers">Category</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Commons page"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/20px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/40px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span> <a href="https://commons.wikimedia.org/wiki/Category:DEC_computer_hardware" class="extiw" title="commons:Category:DEC computer hardware">Commons</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /></div><div role="navigation" class="navbox" aria-labelledby="Compaq1001" style="padding:3px"><table class="nowraplinks hlist mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Compaq" title="Template:Compaq"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Compaq" title="Template talk:Compaq"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Compaq" title="Special:EditPage/Template:Compaq"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Compaq1001" style="font-size:114%;margin:0 4em"><a href="/wiki/Compaq" title="Compaq">Compaq</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="3"><div> <ul><li>Acquired by <a href="/wiki/Hewlett-Packard" title="Hewlett-Packard">Hewlett-Packard</a> in 2002; existing product lines and intellectual property split between <a href="/wiki/HP_Inc." title="HP Inc.">HP Inc.</a> and <a href="/wiki/Hewlett_Packard_Enterprise" title="Hewlett Packard Enterprise">Hewlett Packard Enterprise</a> in 2015</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Corporate<br />aspects</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Founders</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Rod_Canion" title="Rod Canion">Rod Canion</a></li> <li><a href="/wiki/Jim_Harris_(entrepreneur)" title="Jim Harris (entrepreneur)">Jim Harris</a></li> <li><a href="/wiki/Bill_Murto" class="mw-redirect" title="Bill Murto">Bill Murto</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Directors</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Benjamin_M._Rosen" title="Benjamin M. Rosen">Ben Rosen</a></li> <li><a href="/wiki/Michael_Capellas" title="Michael Capellas">Michael Capellas</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Acquisitions</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Thomas-Conrad" title="Thomas-Conrad">Thomas-Conrad</a> (1995)</li> <li><a href="/wiki/NetWorth" title="NetWorth">NetWorth</a> (1995)</li> <li><a href="/wiki/Microcom" title="Microcom">Microcom</a> (1997)</li> <li><a href="/wiki/Tandem_Computers" title="Tandem Computers">Tandem Computers</a> (1997)</li> <li><a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> (1998)</li> <li><a href="/wiki/Zip2" title="Zip2">Zip2</a> (1999)</li></ul> </div></td></tr></tbody></table><div></div></td><td class="noviewer navbox-image" rowspan="3" style="width:1px;padding:0 0 0 2px"><div><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Compaq_logo_1993.svg" class="mw-file-description" title="Compaq logo"><img alt="Compaq logo" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ab/Compaq_logo_1993.svg/110px-Compaq_logo_1993.svg.png" decoding="async" width="110" height="20" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ab/Compaq_logo_1993.svg/165px-Compaq_logo_1993.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ab/Compaq_logo_1993.svg/220px-Compaq_logo_1993.svg.png 2x" data-file-width="1665" data-file-height="309" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Hardware</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Servers</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_SystemPro" title="Compaq SystemPro">SystemPro XL</a></li> <li><a href="/wiki/ProLiant" title="ProLiant">ProLiant</a>*</li> <li><a href="/wiki/NonStop_(server_computers)" title="NonStop (server computers)">NonStop</a>*</li> <li><a href="/wiki/AlphaServer" title="AlphaServer">AlphaServer</a>*</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Workstations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_SystemPro" title="Compaq SystemPro">SystemPro</a></li> <li><a href="/wiki/Compaq_ProSignia" title="Compaq ProSignia">ProSignia</a></li> <li><a href="/wiki/Compaq_Professional_Workstation" title="Compaq Professional Workstation">Professional Workstation</a></li> <li><a href="/wiki/AlphaStation" title="AlphaStation">AlphaStation</a>*</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Desktops</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Business</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_Deskpro" title="Compaq Deskpro">Deskpro</a> <ul><li><a href="/wiki/Compaq_Deskpro_386" title="Compaq Deskpro 386">386</a></li></ul></li> <li><a href="/wiki/Compaq_ProLinea" title="Compaq ProLinea">ProLinea</a></li> <li><a href="/wiki/Compaq_Evo" title="Compaq Evo">Evo</a>*</li> <li><a href="/wiki/HP_Compaq" class="mw-redirect" title="HP Compaq">HP Compaq</a>** <ul><li><a href="/wiki/HP_Compaq_Elite" class="mw-redirect" title="HP Compaq Elite">Elite</a>**</li> <li><a href="/wiki/HP_Compaq_Pro" class="mw-redirect" title="HP Compaq Pro">Pro</a>**</li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Consumer</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_Presario" title="Compaq Presario">Presario</a>*</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Portables<br />and laptops</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Business</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_Portable_series" title="Compaq Portable series">Portable</a> <ul><li><a href="/wiki/Compaq_Portable" title="Compaq Portable">1st generation</a> <ul><li><a href="/wiki/Compaq_Portable_Plus" class="mw-redirect" title="Compaq Portable Plus">Plus</a></li> <li><a href="/wiki/Compaq_Portable_286" class="mw-redirect" title="Compaq Portable 286">286</a></li></ul></li> <li><a href="/wiki/Compaq_Portable_II" title="Compaq Portable II">II</a></li> <li><a href="/wiki/Compaq_Portable_III" title="Compaq Portable III">III</a></li> <li><a href="/wiki/Compaq_Portable_386" title="Compaq Portable 386">386</a></li> <li><a href="/wiki/Compaq_Portable_486" title="Compaq Portable 486">486</a></li></ul></li> <li><a href="/wiki/Compaq_SLT" title="Compaq SLT">SLT</a></li> <li><a href="/wiki/Compaq_LTE" title="Compaq LTE">LTE</a> <ul><li><a href="/wiki/Compaq_LTE_(1st_generation)" title="Compaq LTE (1st generation)">1st generation</a></li> <li><a href="/wiki/Compaq_LTE_Lite" title="Compaq LTE Lite">Lite</a></li> <li><a href="/wiki/Compaq_LTE_Elite" title="Compaq LTE Elite">Elite</a></li> <li><a href="/wiki/Compaq_LTE_5000_series" title="Compaq LTE 5000 series">5000 series</a></li></ul></li> <li><a href="/wiki/Compaq_ProSignia" title="Compaq ProSignia">ProSignia</a></li> <li><a href="/wiki/Compaq_Armada" title="Compaq Armada">Armada</a></li> <li><a href="/wiki/Compaq_Evo" title="Compaq Evo">Evo</a>*</li> <li><a href="/wiki/HP_Compaq" class="mw-redirect" title="HP Compaq">HP Compaq</a>**</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Consumer</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_Contura" title="Compaq Contura">Contura</a></li> <li><a href="/wiki/Compaq_Presario" title="Compaq Presario">Presario</a>* <ul><li><a href="/wiki/Compaq_Presario_1200" title="Compaq Presario 1200">1200</a></li> <li><a href="/wiki/Compaq_Presario_R3000" title="Compaq Presario R3000">R3000</a>**</li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Internet appliances</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MSN_Companion" title="MSN Companion">MSN Companion</a></li> <li><a href="/wiki/IPAQ_(desktop_computer)" title="IPAQ (desktop computer)">iPAQ desktop</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Handhelds<br />and subnotebooks</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compaq_Concerto" title="Compaq Concerto">Concerto</a></li> <li><a href="/wiki/Compaq_Contura_Aero" class="mw-redirect" title="Compaq Contura Aero">Contura Aero</a></li> <li><a href="/wiki/Compaq_Aero" class="mw-redirect" title="Compaq Aero">Aero</a></li> <li><a href="/wiki/Compaq_C_series" title="Compaq C series">C series</a></li> <li><a href="/wiki/Compaq_tc1000" title="Compaq tc1000">tc1000</a></li> <li><a href="/wiki/IPAQ" title="IPAQ">iPAQ handheld</a>*</li> <li><a href="/wiki/HP_Compaq_tc1100" title="HP Compaq tc1100">tc1100</a>**</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Architectures</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">DEC Alpha</a>*</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Software</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AltaVista" title="AltaVista">AltaVista</a></li> <li><a href="/wiki/OpenVMS" title="OpenVMS">OpenVMS</a></li> <li><a href="/wiki/TACL_(programming_language)" title="TACL (programming language)">TACL</a></li> <li><a href="/wiki/Tru64_UNIX" title="Tru64 UNIX">Tru64 UNIX</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="3"><div><div class="hlist"> <ul><li>Asterisk (*) denotes product lines continued after acquisition by HP</li> <li>Double asterisk (**) denotes product lines established after acquisition by HP</li></ul> </div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Template"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/16px-Symbol_template_class_pink.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/23px-Symbol_template_class_pink.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/31px-Symbol_template_class_pink.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Template:DEC_hardware" title="Template:DEC hardware">DEC hardware</a> <ul><li><span class="noviewer" typeof="mw:File"><span title="Template"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/16px-Symbol_template_class_pink.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/23px-Symbol_template_class_pink.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/31px-Symbol_template_class_pink.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Template:DEC_video_terminals" class="mw-redirect" title="Template:DEC video terminals">video terminals</a></li></ul></li> <li><span class="noviewer" typeof="mw:File"><span title="Template"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/16px-Symbol_template_class_pink.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/23px-Symbol_template_class_pink.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/31px-Symbol_template_class_pink.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Template:DEC_operating_systems" class="mw-redirect" title="Template:DEC operating systems">DEC operating systems</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Template"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/16px-Symbol_template_class_pink.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/23px-Symbol_template_class_pink.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/31px-Symbol_template_class_pink.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Template:HP" title="Template:HP">HP</a></li></ul></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Reduced_instruction_set_computer_(RISC)_architectures109" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:RISC_architectures" title="Template:RISC architectures"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:RISC_architectures" title="Template talk:RISC architectures"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:RISC_architectures" title="Special:EditPage/Template:RISC architectures"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Reduced_instruction_set_computer_(RISC)_architectures109" style="font-size:114%;margin:0 4em"><a href="/wiki/Reduced_instruction_set_computer" title="Reduced instruction set computer">Reduced instruction set computer</a> (RISC) architectures</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Origins</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IBM_801" title="IBM 801">IBM 801</a></li> <li><a href="/wiki/Berkeley_RISC" title="Berkeley RISC">Berkeley RISC</a></li> <li><a href="/wiki/Stanford_MIPS" title="Stanford MIPS">Stanford MIPS</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">In active development</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Analog_Devices" title="Analog Devices">Analog Devices</a> <a href="/wiki/Blackfin" title="Blackfin">Blackfin</a></li> <li><a href="/wiki/ARC_(processor)" title="ARC (processor)">ARC</a></li> <li><a href="/wiki/ARM_architecture_family" title="ARM architecture family">ARM</a></li> <li><a href="/wiki/AVR_microcontrollers" title="AVR microcontrollers">AVR</a></li> <li><a href="/wiki/ESi-RISC" title="ESi-RISC">eSi-RISC</a></li> <li><a href="/wiki/LatticeMico8" title="LatticeMico8">LatticeMico8</a>, <a href="/wiki/LatticeMico32" title="LatticeMico32">LatticeMico32</a></li> <li><a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS</a></li> <li><a href="/wiki/OpenRISC" title="OpenRISC">OpenRISC</a></li> <li><a href="/wiki/Power_ISA" title="Power ISA">Power ISA</a></li> <li><a href="/wiki/Renesas_Electronics" title="Renesas Electronics">Renesas</a> <a href="/wiki/M32R" title="M32R">M32R</a>, <a href="/wiki/SuperH" title="SuperH">SuperH</a>, <a href="/wiki/V850" title="V850">V850</a></li> <li><a href="/wiki/RISC-V" title="RISC-V">RISC-V</a></li> <li><a href="/wiki/SPARC" title="SPARC">SPARC</a></li> <li><a href="/wiki/Sunway_(processor)" title="Sunway (processor)">Sunway</a></li> <li><a href="/wiki/Unicore" title="Unicore">Unicore</a></li> <li><a href="/wiki/Xilinx" title="Xilinx">Xilinx</a> <a href="/wiki/MicroBlaze" title="MicroBlaze">MicroBlaze</a>, <a href="/wiki/PicoBlaze" title="PicoBlaze">PicoBlaze</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Development discontinued</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">Alpha</a></li> <li><a href="/wiki/AMD_Am29000" title="AMD Am29000">AMD Am29000</a></li> <li><a href="/wiki/Apollo_PRISM" title="Apollo PRISM">Apollo PRISM</a></li> <li><a href="/wiki/Atmel" title="Atmel">Atmel</a> <a href="/wiki/AVR32" title="AVR32">AVR32</a></li> <li><a href="/wiki/Clipper_architecture" title="Clipper architecture">Clipper</a></li> <li><a href="/wiki/CompactRISC" title="CompactRISC">CR16</a></li> <li><a href="/wiki/AT%26T_Hobbit" title="AT&T Hobbit">CRISP</a></li> <li><a href="/wiki/DEC_PRISM" title="DEC PRISM">DEC PRISM</a></li> <li><a href="/wiki/Intel_i860" title="Intel i860">Intel i860</a>, <a href="/wiki/Intel_i960" title="Intel i960">i960</a></li> <li><a href="/wiki/Imagination_META" title="Imagination META">META</a></li> <li><a href="/wiki/MIPS-X" title="MIPS-X">MIPS-X</a></li> <li><a href="/wiki/Motorola_88000" title="Motorola 88000">Motorola 88000</a>, <a href="/wiki/M%C2%B7CORE" title="M·CORE">M·CORE</a></li> <li><a href="/wiki/PA-RISC" title="PA-RISC">PA-RISC</a></li> <li><a href="/wiki/IBM_POWER_architecture" title="IBM POWER architecture">POWER</a>, <a href="/wiki/PowerPC" title="PowerPC">PowerPC</a> <i>(active use in space exploration as <a href="/wiki/RAD750" title="RAD750">RAD750</a>)</i>, <a href="/wiki/IBM_ROMP" title="IBM ROMP">ROMP</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Processor_technologies439" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Processor_technologies" title="Template:Processor technologies"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Processor_technologies" title="Template talk:Processor technologies"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Processor_technologies" title="Special:EditPage/Template:Processor technologies"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Processor_technologies439" style="font-size:114%;margin:0 4em"><a href="/wiki/Processor_(computing)" title="Processor (computing)">Processor technologies</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Model_of_computation" title="Model of computation">Models</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abstract_machine" title="Abstract machine">Abstract machine</a></li> <li><a href="/wiki/Stored-program_computer" title="Stored-program computer">Stored-program computer</a></li> <li><a href="/wiki/Finite-state_machine" title="Finite-state machine">Finite-state machine</a> <ul><li><a href="/wiki/Finite-state_machine_with_datapath" class="mw-redirect" title="Finite-state machine with datapath">with datapath</a></li> <li><a href="/wiki/Hierarchical_state_machine" class="mw-redirect" title="Hierarchical state machine">Hierarchical</a></li> <li><a href="/wiki/Deterministic_finite_automaton" title="Deterministic finite automaton">Deterministic finite automaton</a></li> <li><a href="/wiki/Queue_automaton" title="Queue automaton">Queue automaton</a></li> <li><a href="/wiki/Cellular_automaton" title="Cellular automaton">Cellular automaton</a></li> <li><a href="/wiki/Quantum_cellular_automaton" title="Quantum cellular automaton">Quantum cellular automaton</a></li></ul></li> <li><a href="/wiki/Turing_machine" title="Turing machine">Turing machine</a> <ul><li><a href="/wiki/Alternating_Turing_machine" title="Alternating Turing machine">Alternating Turing machine</a></li> <li><a href="/wiki/Universal_Turing_machine" title="Universal Turing machine">Universal</a></li> <li><a href="/wiki/Post%E2%80%93Turing_machine" title="Post–Turing machine">Post–Turing</a></li> <li><a href="/wiki/Quantum_Turing_machine" title="Quantum Turing machine">Quantum</a></li> <li><a href="/wiki/Nondeterministic_Turing_machine" title="Nondeterministic Turing machine">Nondeterministic Turing machine</a></li> <li><a href="/wiki/Probabilistic_Turing_machine" title="Probabilistic Turing machine">Probabilistic Turing machine</a></li> <li><a href="/wiki/Hypercomputation" title="Hypercomputation">Hypercomputation</a></li> <li><a href="/wiki/Zeno_machine" title="Zeno machine">Zeno machine</a></li></ul></li> <li><a href="/wiki/History_of_general-purpose_CPUs#Belt_machine_architecture" title="History of general-purpose CPUs">Belt machine</a></li> <li><a href="/wiki/Stack_machine" title="Stack machine">Stack machine</a></li> <li><a href="/wiki/Register_machine" title="Register machine">Register machines</a> <ul><li><a href="/wiki/Counter_machine" title="Counter machine">Counter</a></li> <li><a href="/wiki/Pointer_machine" title="Pointer machine">Pointer</a></li> <li><a href="/wiki/Random-access_machine" title="Random-access machine">Random-access</a></li> <li><a href="/wiki/Random-access_stored-program_machine" title="Random-access stored-program machine">Random-access stored program</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Computer_architecture" title="Computer architecture">Architecture</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Microarchitecture" title="Microarchitecture">Microarchitecture</a></li> <li><a href="/wiki/Von_Neumann_architecture" title="Von Neumann architecture">Von Neumann</a></li> <li><a href="/wiki/Harvard_architecture" title="Harvard architecture">Harvard</a> <ul><li><a href="/wiki/Modified_Harvard_architecture" title="Modified Harvard architecture">modified</a></li></ul></li> <li><a href="/wiki/Dataflow_architecture" title="Dataflow architecture">Dataflow</a></li> <li><a href="/wiki/Transport_triggered_architecture" title="Transport triggered architecture">Transport-triggered</a></li> <li><a href="/wiki/Cellular_architecture" title="Cellular architecture">Cellular</a></li> <li><a href="/wiki/Endianness" title="Endianness">Endianness</a></li> <li><a href="/wiki/Computer_data_storage" title="Computer data storage">Memory access</a> <ul><li><a href="/wiki/Non-uniform_memory_access" title="Non-uniform memory access">NUMA</a></li> <li><a href="/wiki/Uniform_memory_access" title="Uniform memory access">HUMA</a></li> <li><a href="/wiki/Load%E2%80%93store_architecture" title="Load–store architecture">Load–store</a></li> <li><a href="/wiki/Register%E2%80%93memory_architecture" title="Register–memory architecture">Register/memory</a></li></ul></li> <li><a href="/wiki/Cache_hierarchy" title="Cache hierarchy">Cache hierarchy</a></li> <li><a href="/wiki/Memory_hierarchy" title="Memory hierarchy">Memory hierarchy</a> <ul><li><a href="/wiki/Virtual_memory" title="Virtual memory">Virtual memory</a></li> <li><a href="/wiki/Secondary_storage" class="mw-redirect" title="Secondary storage">Secondary storage</a></li></ul></li> <li><a href="/wiki/Heterogeneous_System_Architecture" title="Heterogeneous System Architecture">Heterogeneous</a></li> <li><a href="/wiki/Fabric_computing" title="Fabric computing">Fabric</a></li> <li><a href="/wiki/Multiprocessing" title="Multiprocessing">Multiprocessing</a></li> <li><a href="/wiki/Cognitive_computing" title="Cognitive computing">Cognitive</a></li> <li><a href="/wiki/Neuromorphic_engineering" class="mw-redirect" title="Neuromorphic engineering">Neuromorphic</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Instruction_set_architecture" title="Instruction set architecture">Instruction set<br />architectures</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Types</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Orthogonal_instruction_set" title="Orthogonal instruction set">Orthogonal instruction set</a></li> <li><a href="/wiki/Complex_instruction_set_computer" title="Complex instruction set computer">CISC</a></li> <li><a href="/wiki/Reduced_instruction_set_computer" title="Reduced instruction set computer">RISC</a></li> <li><a href="/wiki/Application-specific_instruction_set_processor" title="Application-specific instruction set processor">Application-specific</a></li> <li><a href="/wiki/Explicit_data_graph_execution" title="Explicit data graph execution">EDGE</a> <ul><li><a href="/wiki/TRIPS_architecture" title="TRIPS architecture">TRIPS</a></li></ul></li> <li><a href="/wiki/Very_long_instruction_word" title="Very long instruction word">VLIW</a> <ul><li><a href="/wiki/Explicitly_parallel_instruction_computing" title="Explicitly parallel instruction computing">EPIC</a></li></ul></li> <li><a href="/wiki/Minimal_instruction_set_computer" title="Minimal instruction set computer">MISC</a></li> <li><a href="/wiki/One-instruction_set_computer" title="One-instruction set computer">OISC</a></li> <li><a href="/wiki/No_instruction_set_computing" title="No instruction set computing">NISC</a></li> <li><a href="/wiki/Zero_instruction_set_computer" class="mw-redirect" title="Zero instruction set computer">ZISC</a></li> <li><a href="/wiki/VISC_architecture" title="VISC architecture">VISC architecture</a></li> <li><a href="/wiki/Quantum_computing" title="Quantum computing">Quantum computing</a></li> <li><a href="/wiki/Comparison_of_instruction_set_architectures" title="Comparison of instruction set architectures">Comparison</a> <ul><li><a href="/wiki/Addressing_mode" title="Addressing mode">Addressing modes</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Instruction<br />sets</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Motorola_68000_series" title="Motorola 68000 series">Motorola 68000 series</a></li> <li><a href="/wiki/VAX" title="VAX">VAX</a></li> <li><a href="/wiki/PDP-11_architecture" title="PDP-11 architecture">PDP-11</a></li> <li><a href="/wiki/X86" title="X86">x86</a></li> <li><a href="/wiki/ARM_architecture_family" title="ARM architecture family">ARM</a></li> <li><a href="/wiki/Stanford_MIPS" title="Stanford MIPS">Stanford MIPS</a></li> <li><a href="/wiki/MIPS_architecture" title="MIPS architecture">MIPS</a></li> <li><a href="/wiki/MIPS-X" title="MIPS-X">MIPS-X</a></li> <li>Power <ul><li><a href="/wiki/IBM_POWER_architecture" title="IBM POWER architecture">POWER</a></li> <li><a href="/wiki/PowerPC" title="PowerPC">PowerPC</a></li> <li><a href="/wiki/Power_ISA" title="Power ISA">Power ISA</a></li></ul></li> <li><a href="/wiki/Clipper_architecture" title="Clipper architecture">Clipper architecture</a></li> <li><a href="/wiki/SPARC" title="SPARC">SPARC</a></li> <li><a href="/wiki/SuperH" title="SuperH">SuperH</a></li> <li><a class="mw-selflink selflink">DEC Alpha</a></li> <li><a href="/wiki/ETRAX_CRIS" title="ETRAX CRIS">ETRAX CRIS</a></li> <li><a href="/wiki/M32R" title="M32R">M32R</a></li> <li><a href="/wiki/Unicore" title="Unicore">Unicore</a></li> <li><a href="/wiki/IA-64" title="IA-64">Itanium</a></li> <li><a href="/wiki/OpenRISC" title="OpenRISC">OpenRISC</a></li> <li><a href="/wiki/RISC-V" title="RISC-V">RISC-V</a></li> <li><a href="/wiki/MicroBlaze" title="MicroBlaze">MicroBlaze</a></li> <li><a href="/wiki/Little_man_computer" title="Little man computer">LMC</a></li> <li>System/3x0 <ul><li><a href="/wiki/IBM_System/360_architecture" title="IBM System/360 architecture">S/360</a></li> <li><a href="/wiki/IBM_System/370" title="IBM System/370">S/370</a></li> <li><a href="/wiki/IBM_System/390" title="IBM System/390">S/390</a></li> <li><a href="/wiki/Z/Architecture" title="Z/Architecture">z/Architecture</a></li></ul></li> <li>Tilera ISA</li> <li><a href="/wiki/VISC_architecture" title="VISC architecture">VISC architecture</a></li> <li><a href="/wiki/Adapteva#Products" class="mw-redirect" title="Adapteva">Epiphany architecture</a></li> <li><a href="/wiki/Comparison_of_instruction_set_architectures" title="Comparison of instruction set architectures">Others</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Instruction_cycle" title="Instruction cycle">Execution</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Instruction_pipelining" title="Instruction pipelining">Instruction pipelining</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Pipeline_stall" title="Pipeline stall">Pipeline stall</a></li> <li><a href="/wiki/Operand_forwarding" title="Operand forwarding">Operand forwarding</a></li> <li><a href="/wiki/Classic_RISC_pipeline" title="Classic RISC pipeline">Classic RISC pipeline</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Hazard_(computer_architecture)" title="Hazard (computer architecture)">Hazards</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Data_dependency" title="Data dependency">Data dependency</a></li> <li><a href="/wiki/Structural_hazard" class="mw-redirect" title="Structural hazard">Structural</a></li> <li><a href="/wiki/Control_hazard" class="mw-redirect" title="Control hazard">Control</a></li> <li><a href="/wiki/False_sharing" title="False sharing">False sharing</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Out-of-order_execution" title="Out-of-order execution">Out-of-order</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Scoreboarding" title="Scoreboarding">Scoreboarding</a></li> <li><a href="/wiki/Tomasulo%27s_algorithm" title="Tomasulo's algorithm">Tomasulo's algorithm</a> <ul><li><a href="/wiki/Reservation_station" title="Reservation station">Reservation station</a></li> <li><a href="/wiki/Re-order_buffer" title="Re-order buffer">Re-order buffer</a></li></ul></li> <li><a href="/wiki/Register_renaming" title="Register renaming">Register renaming</a></li> <li><a href="/wiki/Wide-issue" title="Wide-issue">Wide-issue</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Speculative_execution" title="Speculative execution">Speculative</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Branch_predictor" title="Branch predictor">Branch prediction</a></li> <li><a href="/wiki/Memory_dependence_prediction" title="Memory dependence prediction">Memory dependence prediction</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Parallel_computing" title="Parallel computing">Parallelism</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Level</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bit-level_parallelism" title="Bit-level parallelism">Bit</a> <ul><li><a href="/wiki/Bit-serial_architecture" title="Bit-serial architecture">Bit-serial</a></li> <li><a href="/wiki/Word_(computer_architecture)" title="Word (computer architecture)">Word</a></li></ul></li> <li><a href="/wiki/Instruction-level_parallelism" title="Instruction-level parallelism">Instruction</a></li> <li><a href="/wiki/Instruction_pipelining" title="Instruction pipelining">Pipelining</a> <ul><li><a href="/wiki/Scalar_processor" title="Scalar processor">Scalar</a></li> <li><a href="/wiki/Superscalar_processor" title="Superscalar processor">Superscalar</a></li></ul></li> <li><a href="/wiki/Task_parallelism" title="Task parallelism">Task</a> <ul><li><a href="/wiki/Thread_(computing)" title="Thread (computing)">Thread</a></li> <li><a href="/wiki/Process_(computing)" title="Process (computing)">Process</a></li></ul></li> <li><a href="/wiki/Data_parallelism" title="Data parallelism">Data</a> <ul><li><a href="/wiki/Vector_processor" title="Vector processor">Vector</a></li></ul></li> <li><a href="/wiki/Memory-level_parallelism" title="Memory-level parallelism">Memory</a></li> <li><a href="/wiki/Distributed_architecture" class="mw-redirect" title="Distributed architecture">Distributed</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Multithreading_(computer_architecture)" title="Multithreading (computer architecture)">Multithreading</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Temporal_multithreading" title="Temporal multithreading">Temporal</a></li> <li><a href="/wiki/Simultaneous_multithreading" title="Simultaneous multithreading">Simultaneous</a> <ul><li><a href="/wiki/Hyper-threading" title="Hyper-threading">Hyperthreading</a></li> <li><a href="/wiki/Simultaneous_and_heterogeneous_multithreading" title="Simultaneous and heterogeneous multithreading">Simultaneous and heterogenous</a></li></ul></li> <li><a href="/wiki/Speculative_multithreading" title="Speculative multithreading">Speculative</a></li> <li><a href="/wiki/Preemption_(computing)" title="Preemption (computing)">Preemptive</a></li> <li><a href="/wiki/Cooperative_multitasking" title="Cooperative multitasking">Cooperative</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Flynn%27s_taxonomy" title="Flynn's taxonomy">Flynn's taxonomy</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Single_instruction,_single_data" title="Single instruction, single data">SISD</a></li> <li><a href="/wiki/Single_instruction,_multiple_data" title="Single instruction, multiple data">SIMD</a> <ul><li><a href="/wiki/Single_instruction,_multiple_threads" title="Single instruction, multiple threads">Array processing (SIMT)</a></li> <li><a href="/wiki/Flynn%27s_taxonomy#Pipelined_processor" title="Flynn's taxonomy">Pipelined processing</a></li> <li><a href="/wiki/Flynn%27s_taxonomy#Associative_processor" title="Flynn's taxonomy">Associative processing</a></li> <li><a href="/wiki/SWAR" title="SWAR">SWAR</a></li></ul></li> <li><a href="/wiki/Multiple_instruction,_single_data" title="Multiple instruction, single data">MISD</a></li> <li><a href="/wiki/Multiple_instruction,_multiple_data" title="Multiple instruction, multiple data">MIMD</a> <ul><li><a href="/wiki/Single_program,_multiple_data" title="Single program, multiple data">SPMD</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Computer_performance" title="Computer performance">Processor<br />performance</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Transistor_count" title="Transistor count">Transistor count</a></li> <li><a href="/wiki/Instructions_per_cycle" title="Instructions per cycle">Instructions per cycle</a> (IPC) <ul><li><a href="/wiki/Cycles_per_instruction" title="Cycles per instruction">Cycles per instruction</a> (CPI)</li></ul></li> <li><a href="/wiki/Instructions_per_second" title="Instructions per second">Instructions per second</a> (IPS)</li> <li><a href="/wiki/FLOPS" class="mw-redirect" title="FLOPS">Floating-point operations per second</a> (FLOPS)</li> <li><a href="/wiki/Transactions_per_second" title="Transactions per second">Transactions per second</a> (TPS)</li> <li><a href="/wiki/SUPS" title="SUPS">Synaptic updates per second</a> (SUPS)</li> <li><a href="/wiki/Performance_per_watt" title="Performance per watt">Performance per watt</a> (PPW)</li> <li><a href="/wiki/Cache_performance_measurement_and_metric" title="Cache performance measurement and metric">Cache performance metrics</a></li> <li><a href="/wiki/Computer_performance_by_orders_of_magnitude" title="Computer performance by orders of magnitude">Computer performance by orders of magnitude</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Processor_(computing)" title="Processor (computing)">Types</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Central_processing_unit" title="Central processing unit">Central processing unit</a> (CPU)</li> <li><a href="/wiki/Graphics_processing_unit" title="Graphics processing unit">Graphics processing unit</a> (GPU) <ul><li><a href="/wiki/General-purpose_computing_on_graphics_processing_units" title="General-purpose computing on graphics processing units">GPGPU</a></li></ul></li> <li><a href="/wiki/Vector_processor" title="Vector processor">Vector</a></li> <li><a href="/wiki/Barrel_processor" title="Barrel processor">Barrel</a></li> <li><a href="/wiki/Stream_processing" title="Stream processing">Stream</a></li> <li><a href="/wiki/Tile_processor" title="Tile processor">Tile processor</a></li> <li><a href="/wiki/Coprocessor" title="Coprocessor">Coprocessor</a></li> <li><a href="/wiki/Programmable_Array_Logic" title="Programmable Array Logic">PAL</a></li> <li><a href="/wiki/Application-specific_integrated_circuit" title="Application-specific integrated circuit">ASIC</a></li> <li><a href="/wiki/Field-programmable_gate_array" title="Field-programmable gate array">FPGA</a></li> <li><a href="/wiki/Field-programmable_object_array" title="Field-programmable object array">FPOA</a></li> <li><a href="/wiki/Complex_programmable_logic_device" title="Complex programmable logic device">CPLD</a></li> <li><a href="/wiki/Multi-chip_module" title="Multi-chip module">Multi-chip module</a> (MCM)</li> <li><a href="/wiki/System_in_a_package" title="System in a package">System in a package</a> (SiP)</li> <li><a href="/wiki/Package_on_a_package" title="Package on a package">Package on a package</a> (PoP)</li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">By application</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Embedded_system" title="Embedded system">Embedded system</a></li> <li><a href="/wiki/Microprocessor" title="Microprocessor">Microprocessor</a></li> <li><a href="/wiki/Microcontroller" title="Microcontroller">Microcontroller</a></li> <li><a href="/wiki/Mobile_processor" title="Mobile processor">Mobile</a></li> <li><a href="/wiki/Ultra-low-voltage_processor" title="Ultra-low-voltage processor">Ultra-low-voltage</a></li> <li><a href="/wiki/Application-specific_instruction_set_processor" title="Application-specific instruction set processor">ASIP</a></li> <li><a href="/wiki/Soft_microprocessor" title="Soft microprocessor">Soft microprocessor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Systems<br />on chip</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/System_on_a_chip" title="System on a chip">System on a chip</a> (SoC)</li> <li><a href="/wiki/Multiprocessor_system_on_a_chip" class="mw-redirect" title="Multiprocessor system on a chip">Multiprocessor</a> (MPSoC)</li> <li><a href="/wiki/Cypress_PSoC" title="Cypress PSoC">Cypress PSoC</a></li> <li><a href="/wiki/Network_on_a_chip" title="Network on a chip">Network on a chip</a> (NoC)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Hardware_acceleration" title="Hardware acceleration">Hardware<br />accelerators</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Coprocessor" title="Coprocessor">Coprocessor</a></li> <li><a href="/wiki/AI_accelerator" class="mw-redirect" title="AI accelerator">AI accelerator</a></li> <li><a href="/wiki/Graphics_processing_unit" title="Graphics processing unit">Graphics processing unit</a> (GPU)</li> <li><a href="/wiki/Image_processor" title="Image processor">Image processor</a></li> <li><a href="/wiki/Vision_processing_unit" title="Vision processing unit">Vision processing unit</a> (VPU)</li> <li><a href="/wiki/Physics_processing_unit" title="Physics processing unit">Physics processing unit</a> (PPU)</li> <li><a href="/wiki/Digital_signal_processor" title="Digital signal processor">Digital signal processor</a> (DSP)</li> <li><a href="/wiki/Tensor_Processing_Unit" title="Tensor Processing Unit">Tensor Processing Unit</a> (TPU)</li> <li><a href="/wiki/Secure_cryptoprocessor" title="Secure cryptoprocessor">Secure cryptoprocessor</a></li> <li><a href="/wiki/Network_processor" title="Network processor">Network processor</a></li> <li><a href="/wiki/Baseband_processor" title="Baseband processor">Baseband processor</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Word_(computer_architecture)" title="Word (computer architecture)">Word size</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/1-bit_computing" title="1-bit computing">1-bit</a></li> <li><a href="/wiki/4-bit_computing" title="4-bit computing">4-bit</a></li> <li><a href="/wiki/8-bit_computing" title="8-bit computing">8-bit</a></li> <li><a href="/wiki/12-bit_computing" title="12-bit computing">12-bit</a></li> <li><a href="/wiki/Apollo_Guidance_Computer" title="Apollo Guidance Computer">15-bit</a></li> <li><a href="/wiki/16-bit_computing" title="16-bit computing">16-bit</a></li> <li><a href="/wiki/24-bit_computing" title="24-bit computing">24-bit</a></li> <li><a href="/wiki/32-bit_computing" title="32-bit computing">32-bit</a></li> <li><a href="/wiki/48-bit_computing" title="48-bit computing">48-bit</a></li> <li><a href="/wiki/64-bit_computing" title="64-bit computing">64-bit</a></li> <li><a href="/wiki/128-bit_computing" title="128-bit computing">128-bit</a></li> <li><a href="/wiki/256-bit_computing" title="256-bit computing">256-bit</a></li> <li><a href="/wiki/512-bit_computing" title="512-bit computing">512-bit</a></li> <li><a href="/wiki/Bit_slicing" title="Bit slicing">bit slicing</a></li> <li><a href="/wiki/Word_(computer_architecture)#Table_of_word_sizes" title="Word (computer architecture)">others</a> <ul><li><a href="/wiki/Word_(computer_architecture)#Variable-word_architectures" title="Word (computer architecture)">variable</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Core count</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Single-core" title="Single-core">Single-core</a></li> <li><a href="/wiki/Multi-core_processor" title="Multi-core processor">Multi-core</a></li> <li><a href="/wiki/Manycore_processor" title="Manycore processor">Manycore</a></li> <li><a href="/wiki/Heterogeneous_computing" title="Heterogeneous computing">Heterogeneous architecture</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Components</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Central_processing_unit" title="Central processing unit">Core</a></li> <li><a href="/wiki/Cache_(computing)" title="Cache (computing)">Cache</a> <ul><li><a href="/wiki/CPU_cache" title="CPU cache">CPU cache</a></li> <li><a href="/wiki/Scratchpad_memory" title="Scratchpad memory">Scratchpad memory</a></li> <li><a href="/wiki/Data_cache" class="mw-redirect" title="Data cache">Data cache</a></li> <li><a href="/wiki/Instruction_cache" class="mw-redirect" title="Instruction cache">Instruction cache</a></li> <li><a href="/wiki/Cache_replacement_policies" title="Cache replacement policies">replacement policies</a></li> <li><a href="/wiki/Cache_coherence" title="Cache coherence">coherence</a></li></ul></li> <li><a href="/wiki/Bus_(computing)" title="Bus (computing)">Bus</a></li> <li><a href="/wiki/Clock_rate" title="Clock rate">Clock rate</a></li> <li><a href="/wiki/Clock_signal" title="Clock signal">Clock signal</a></li> <li><a href="/wiki/FIFO_(computing_and_electronics)" title="FIFO (computing and electronics)">FIFO</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Execution_unit" title="Execution unit">Functional<br />units</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Arithmetic_logic_unit" title="Arithmetic logic unit">Arithmetic logic unit</a> (ALU)</li> <li><a href="/wiki/Address_generation_unit" title="Address generation unit">Address generation unit</a> (AGU)</li> <li><a href="/wiki/Floating-point_unit" title="Floating-point unit">Floating-point unit</a> (FPU)</li> <li><a href="/wiki/Memory_management_unit" title="Memory management unit">Memory management unit</a> (MMU) <ul><li><a href="/wiki/Load%E2%80%93store_unit" title="Load–store unit">Load–store unit</a></li> <li><a href="/wiki/Translation_lookaside_buffer" title="Translation lookaside buffer">Translation lookaside buffer</a> (TLB)</li></ul></li> <li><a href="/wiki/Branch_predictor" title="Branch predictor">Branch predictor</a></li> <li><a href="/wiki/Branch_target_predictor" title="Branch target predictor">Branch target predictor</a></li> <li><a href="/wiki/Memory_controller" title="Memory controller">Integrated memory controller</a> (IMC) <ul><li><a href="/wiki/Memory_management_unit" title="Memory management unit">Memory management unit</a></li></ul></li> <li><a href="/wiki/Instruction_decoder" class="mw-redirect" title="Instruction decoder">Instruction decoder</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Logic_gate" title="Logic gate">Logic</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Combinational_logic" title="Combinational logic">Combinational</a></li> <li><a href="/wiki/Sequential_logic" title="Sequential logic">Sequential</a></li> <li><a href="/wiki/Glue_logic" title="Glue logic">Glue</a></li> <li><a href="/wiki/Logic_gate" title="Logic gate">Logic gate</a> <ul><li><a href="/wiki/Quantum_logic_gate" title="Quantum logic gate">Quantum</a></li> <li><a href="/wiki/Gate_array" title="Gate array">Array</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Hardware_register" title="Hardware register">Registers</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Processor_register" title="Processor register">Processor register</a></li> <li><a href="/wiki/Status_register" title="Status register">Status register</a></li> <li><a href="/wiki/Stack_register" title="Stack register">Stack register</a></li> <li><a href="/wiki/Register_file" title="Register file">Register file</a></li> <li><a href="/wiki/Memory_buffer_register" title="Memory buffer register">Memory buffer</a></li> <li><a href="/wiki/Memory_address_register" title="Memory address register">Memory address register</a></li> <li><a href="/wiki/Program_counter" title="Program counter">Program counter</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Control_unit" title="Control unit">Control unit</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hardwired_control_unit" class="mw-redirect" title="Hardwired control unit">Hardwired control unit</a></li> <li><a href="/wiki/Instruction_unit" title="Instruction unit">Instruction unit</a></li> <li><a href="/wiki/Data_buffer" title="Data buffer">Data buffer</a></li> <li><a href="/wiki/Write_buffer" title="Write buffer">Write buffer</a></li> <li><a href="/wiki/Microcode" title="Microcode">Microcode</a> <a href="/wiki/ROM_image" title="ROM image">ROM</a></li> <li><a href="/wiki/Counter_(digital)" title="Counter (digital)">Counter</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Datapath" title="Datapath">Datapath</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Multiplexer" title="Multiplexer">Multiplexer</a></li> <li><a href="/wiki/Demultiplexer" class="mw-redirect" title="Demultiplexer">Demultiplexer</a></li> <li><a href="/wiki/Adder_(electronics)" title="Adder (electronics)">Adder</a></li> <li><a href="/wiki/Binary_multiplier" title="Binary multiplier">Multiplier</a> <ul><li><a href="/wiki/CPU_multiplier" title="CPU multiplier">CPU</a></li></ul></li> <li><a href="/wiki/Binary_decoder" title="Binary decoder">Binary decoder</a> <ul><li><a href="/wiki/Address_decoder" title="Address decoder">Address decoder</a></li> <li><a href="/wiki/Sum-addressed_decoder" title="Sum-addressed decoder">Sum-addressed decoder</a></li></ul></li> <li><a href="/wiki/Barrel_shifter" title="Barrel shifter">Barrel shifter</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Electronic_circuit" title="Electronic circuit">Circuitry</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Integrated_circuit" title="Integrated circuit">Integrated circuit</a> <ul><li><a href="/wiki/Three-dimensional_integrated_circuit" title="Three-dimensional integrated circuit">3D</a></li> <li><a href="/wiki/Mixed-signal_integrated_circuit" title="Mixed-signal integrated circuit">Mixed-signal</a></li> <li><a href="/wiki/Power_management_integrated_circuit" title="Power management integrated circuit">Power management</a></li></ul></li> <li><a href="/wiki/Boolean_circuit" title="Boolean circuit">Boolean</a></li> <li><a href="/wiki/Circuit_(computer_science)" title="Circuit (computer science)">Digital</a></li> <li><a href="/wiki/Analogue_electronics" title="Analogue electronics">Analog</a></li> <li><a href="/wiki/Quantum_circuit" title="Quantum circuit">Quantum</a></li> <li><a href="/wiki/Switch#Electronic_switches" title="Switch">Switch</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Power_management" title="Power management">Power<br />management</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Power_Management_Unit" title="Power Management Unit">PMU</a></li> <li><a href="/wiki/Advanced_Power_Management" title="Advanced Power Management">APM</a></li> <li><a href="/wiki/ACPI" title="ACPI">ACPI</a></li> <li><a href="/wiki/Dynamic_frequency_scaling" title="Dynamic frequency scaling">Dynamic frequency scaling</a></li> <li><a href="/wiki/Dynamic_voltage_scaling" title="Dynamic voltage scaling">Dynamic voltage scaling</a></li> <li><a href="/wiki/Clock_gating" title="Clock gating">Clock gating</a></li> <li><a href="/wiki/Performance_per_watt" title="Performance per watt">Performance per watt</a> (PPW)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/History_of_general-purpose_CPUs" title="History of general-purpose CPUs">History of general-purpose CPUs</a></li> <li><a href="/wiki/Microprocessor_chronology" title="Microprocessor chronology">Microprocessor chronology</a></li> <li><a href="/wiki/Processor_design" title="Processor design">Processor design</a></li> <li><a href="/wiki/Digital_electronics" title="Digital electronics">Digital electronics</a></li> <li><a href="/wiki/Hardware_security_module" title="Hardware security module">Hardware security module</a></li> <li><a href="/wiki/Semiconductor_device_fabrication" title="Semiconductor device fabrication">Semiconductor device fabrication</a></li> <li><a href="/wiki/Tick%E2%80%93tock_model" title="Tick–tock model">Tick–tock model</a></li> <li><a href="/wiki/Pin_grid_array" title="Pin grid array">Pin grid array</a></li> <li><a href="/wiki/Chip_carrier" title="Chip carrier">Chip carrier</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox authority-control" aria-label="Navbox580" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control 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