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<li id="toc-Package" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Package"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.7</span> <span>Package</span> </div> </a> <ul id="toc-Package-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Derivatives" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Derivatives"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Derivatives</span> </div> </a> <button aria-controls="toc-Derivatives-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 Derivatives subsection</span> </button> <ul id="toc-Derivatives-sublist" class="vector-toc-list"> <li id="toc-Alpha_21164_(EV56)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Alpha_21164_(EV56)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Alpha 21164 (EV56)</span> </div> </a> <ul id="toc-Alpha_21164_(EV56)-sublist" class="vector-toc-list"> <li id="toc-History_2" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#History_2"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1.1</span> <span>History</span> </div> </a> <ul id="toc-History_2-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Description_2" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Description_2"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1.2</span> <span>Description</span> </div> </a> <ul id="toc-Description_2-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Alpha_21164PC_(PCA56)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Alpha_21164PC_(PCA56)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Alpha 21164PC (PCA56)</span> </div> </a> <ul id="toc-Alpha_21164PC_(PCA56)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Alpha_21164PC_(PCA57)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Alpha_21164PC_(PCA57)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Alpha 21164PC (PCA57)</span> </div> </a> <ul id="toc-Alpha_21164PC_(PCA57)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Chipsets" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Chipsets"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Chipsets</span> </div> </a> <button aria-controls="toc-Chipsets-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 Chipsets subsection</span> </button> <ul id="toc-Chipsets-sublist" class="vector-toc-list"> <li id="toc-21171" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#21171"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>21171</span> </div> </a> <ul id="toc-21171-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-21172" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#21172"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>21172</span> </div> </a> <ul id="toc-21172-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Pyxis" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Pyxis"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Pyxis</span> </div> </a> <ul id="toc-Pyxis-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Polaris" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Polaris"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>Polaris</span> </div> </a> <ul id="toc-Polaris-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</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 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Further_reading" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Further_reading"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Further reading</span> </div> </a> <ul id="toc-Further_reading-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</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 class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" 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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">Microprocessor</div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Processor_board_cray-2_hg.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c2/Processor_board_cray-2_hg.jpg/220px-Processor_board_cray-2_hg.jpg" decoding="async" width="220" height="111" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c2/Processor_board_cray-2_hg.jpg/330px-Processor_board_cray-2_hg.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c2/Processor_board_cray-2_hg.jpg/440px-Processor_board_cray-2_hg.jpg 2x" data-file-width="2232" data-file-height="1128" /></a><figcaption>Four gold-coloured 300 MHz Alpha 21164 microprocessors on a <a href="/wiki/Cray_T3E" title="Cray T3E">Cray T3E-600</a> processor board</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Alpha_EV5_die.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Alpha_EV5_die.JPG/220px-Alpha_EV5_die.JPG" decoding="async" width="220" height="200" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Alpha_EV5_die.JPG/330px-Alpha_EV5_die.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Alpha_EV5_die.JPG/440px-Alpha_EV5_die.JPG 2x" data-file-width="3398" data-file-height="3086" /></a><figcaption>DEC Alpha 21164 (EV5) die shot</figcaption></figure> <p>The <b>Alpha 21164</b>, also known by its code name, <b>EV5</b>, is a <a href="/wiki/Microprocessor" title="Microprocessor">microprocessor</a> developed and fabricated by <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> that implemented the <a href="/wiki/DEC_Alpha" title="DEC Alpha">Alpha</a> <a href="/wiki/Instruction_set_architecture" title="Instruction set architecture">instruction set architecture</a> (ISA). It was introduced in January 1995, succeeding the <a href="/wiki/Alpha_21064" title="Alpha 21064">Alpha 21064A</a> as Digital's flagship microprocessor. It was succeeded by the <a href="/wiki/Alpha_21264" title="Alpha 21264">Alpha 21264</a> in 1998. </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=Alpha_21164&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>First silicon of the Alpha 21164 was produced in February 1994, and the <a href="/wiki/OpenVMS" title="OpenVMS">OpenVMS</a>, <a href="/wiki/Tru64_UNIX" title="Tru64 UNIX">Digital UNIX</a> and <a href="/wiki/Windows_NT" title="Windows NT">Windows NT</a> <a href="/wiki/Operating_system" title="Operating system">operating systems</a> were successfully booted on it. It was sampled in late 1994 and was introduced in January 1995 at 266 MHz. A 300 MHz version was introduced in March 1995. The final Alpha 21164, a 333 MHz version, was announced on 2 October 1995, available in sample quantities. The Alpha 21164 was replaced by the Alpha 21164A as Digital's flagship microprocessor in 1996 when a 400 MHz version became available in volume quantities. </p> <div class="mw-heading mw-heading3"><h3 id="Users">Users</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=2" title="Edit section: Users"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Digital used the Alpha 21164 operating at various clock frequencies in their <a href="/wiki/AlphaServer" title="AlphaServer">AlphaServer</a> <a href="/wiki/Server_(computing)" title="Server (computing)">servers</a>, <a href="/wiki/AlphaStation" title="AlphaStation">AlphaStation</a> <a href="/wiki/Workstation" title="Workstation">workstations</a>. Digital also used the Alpha 21164 in their Alpha VME 5/352 and Alpha VME 5/480 <a href="/wiki/Single_board_computer" class="mw-redirect" title="Single board computer">single board computers</a> and AlphaPC 164 and AlphaPC 164LX <a href="/wiki/Motherboard" title="Motherboard">motherboards</a>. Alpha partner <a href="/wiki/Cray_Research" class="mw-redirect" title="Cray Research">Cray Research</a> used a 300 MHz Alpha 21164 in their <a href="/wiki/Cray_T3E" title="Cray T3E">T3E-600</a> supercomputer. Third parties such as <a href="/wiki/DeskStation" class="mw-redirect" title="DeskStation">DeskStation</a> also built workstations using the Alpha 21164. </p> <div class="mw-heading mw-heading3"><h3 id="Performance">Performance</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=3" title="Edit section: Performance"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 21164 continued the performance lead from the 275 MHz <a href="/wiki/Alpha_21064#Alpha_21064A" title="Alpha 21064">Alpha 21064A</a> until the introduction of the <a href="/wiki/Intel_Corporation" class="mw-redirect" title="Intel Corporation">Intel</a> <a href="/wiki/Pentium_Pro" title="Pentium Pro">Pentium Pro</a> in November 1995, when a 200 MHz version outperformed the 300 MHz 21164 on the <a href="/wiki/SPECint" title="SPECint">SPECint95_base</a> benchmark suite. The 21164 retained its floating-point performance lead. The 333 MHz 21164 introduce the following year outperformed the Pentium Pro, but it was later surpassed by the <a href="/wiki/MIPS_Technologies" title="MIPS Technologies">MIPS Technologies</a> <a href="/wiki/R10000" title="R10000">R10000</a> and then by the <a href="/wiki/Hewlett-Packard" title="Hewlett-Packard">Hewlett-Packard</a> <a href="/wiki/PA-8000" title="PA-8000">PA-8000</a> in the same year.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Description">Description</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=4" title="Edit section: Description"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha 21164 is a four-issue <a href="/wiki/Superscalar" class="mw-redirect" title="Superscalar">superscalar</a> microprocessor capable of issuing a maximum of four instructions per <a href="/wiki/Clock_signal" title="Clock signal">clock cycle</a> to four execution units: two <a href="/wiki/Integer" title="Integer">integer</a> and two <a href="/wiki/Floating-point" class="mw-redirect" title="Floating-point">floating-point</a>. The integer pipeline is seven stages long, and the floating-point pipeline is ten stages long. The 21164 implemented a 43-bit <a href="/wiki/Virtual_address" class="mw-redirect" title="Virtual address">virtual address</a> and a 40-bit <a href="/wiki/Physical_address" title="Physical address">physical address</a>. It was therefore capable of addressing 8 TB of <a href="/wiki/Virtual_memory" title="Virtual memory">virtual memory</a> and 1 TB of <a href="/wiki/Physical_memory" class="mw-redirect" title="Physical memory">physical memory</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Integer_unit">Integer unit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=5" title="Edit section: Integer unit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The integer unit consisted of two integer pipelines and the integer <a href="/wiki/Register_file" title="Register file">register file</a>. The two pipelines, the add pipeline and the multiply pipeline are not identical, each are responsible for executing different instructions, although both are capable of executing common add, logical, load, compare, and conditional move instructions. The multiply pipeline exclusively executes shift, store, and multiply instructions (in a non-pipelined multiplier). The add pipeline exclusively executes branch instructions. </p><p>Except for branch, conditional move, and multiply instructions, all other instructions begin and finish execution during stage five for a one cycle latency. Branch and conditional move instructions are executed during stage six so they can be issued with a compare instruction whose result they depend on. </p><p>The integer register file contained forty 64-bit registers, of which thirty-two are specified by the Alpha Architecture and eight are for use by <a href="/wiki/PALcode" title="PALcode">PALcode</a> as scratchpad memory. The register file has four read ports and two write ports evenly divided between the two integer pipelines.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Floating-point_unit">Floating-point unit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=6" title="Edit section: Floating-point unit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The floating-point unit consisted of two floating-point pipelines and the floating point register file. The two pipelines are not identical, one executed all floating-point instructions except for multiply, and the other executed only multiply instructions. Both pipelines have four stages. A non-pipelined floating-point divider is connected to the add pipeline. All floating-point instructions except for divide have four-cycle latency. Divides have variable latency that depends on whether the operation is being performed on <a href="/wiki/Single_precision" class="mw-redirect" title="Single precision">single</a> or on <a href="/wiki/Double_precision" class="mw-redirect" title="Double precision">double precision</a> floating-point numbers and numbers. Including overhead, single precision divides have a 15- to 31-cycle latency, whereas double precision divides have a 22- to 60-cycle latency. </p> <div class="mw-heading mw-heading3"><h3 id="Cache">Cache</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=7" title="Edit section: Cache"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 21164 has three levels of <a href="/wiki/CPU_cache" title="CPU cache">cache</a>, two on-die and one external and optional. The caches and the associated logic consisted of 7.2 million transistors.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>The primary cache is split into separate caches for instructions and data, referred to as the I-cache and D-cache respectively. They are 8 KB in size, <a href="/wiki/CPU_cache#Associativity" title="CPU cache">direct-mapped</a> and have a cache line size of 32 bytes. The D-cache is dual-ported, to improve performance, and is implemented by duplicating the cache twice. It uses a <a href="/wiki/Write-through" class="mw-redirect" title="Write-through">write-through</a> write policy and an on-read allocation policy. </p><p>The secondary cache, known as the S-cache, is on-die and has a capacity of 96 KB. An on-die secondary cache was required as the 21164 required more bandwidth than an external secondary cache could supply in order to provide it with enough instructions and data.<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> The cache required two cycles to access due to its large area. To improve performance, the cache is pipelined. Another benefit of an on-die secondary cache was that it could be easily implemented as a multi-way cache, and as a result, the cache is three-way <a href="/wiki/CPU_cache#Associativity" title="CPU cache">set associative</a>, offering improved hit rates than direct-mapped caches.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> The S-cache, due to the large physical area required, was implemented in two halves which flank the I-box, E-box, F-box and M-box. This was done so the cache could return data in two cycles. </p><p>The tertiary cache, known as the B-cache, is implemented with external SRAMs. The B-cache was optional and some systems using the Alpha 21164 did not have any. The B-cache could have a capacity of 1 to 64 MB, smaller capacities were not supported as they were rendered useless by the on-die S-cache.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> It is direct-mapped, uses a <a href="/wiki/Write-back" class="mw-redirect" title="Write-back">write-back</a> write policy and an on-write allocation policy. The B-cache is controlled by on-die external interface logic, unlike the 21064, which required an external cache controller. The B-cache could be built with asynchronous or synchronous SRAMs. The B-cache is accessed via the system bus. </p> <div class="mw-heading mw-heading3"><h3 id="External_interface">External interface</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=8" title="Edit section: External interface"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Sockel_499.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Sockel_499.jpg/220px-Sockel_499.jpg" decoding="async" width="220" height="244" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Sockel_499.jpg/330px-Sockel_499.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Sockel_499.jpg/440px-Sockel_499.jpg 2x" data-file-width="1152" data-file-height="1280" /></a><figcaption>Socket 499 for Alpha 21164</figcaption></figure> <p>The external interface is a 128-bit system bus. The system bus operates at a clock frequency that is 3 to 15 times lower than the internal clock frequency, or 20 to 100 MHz with an internal clock frequency 300 MHz. The system bus' clock signal is generated by the microprocessor. </p> <div class="mw-heading mw-heading3"><h3 id="Clock">Clock</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=9" title="Edit section: Clock"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The internal clock frequency is generated by dividing an external clock signal by two. The Alpha 21164 therefore requires an external clock signal of 600 MHz for a 300 MHz Alpha 21164. </p> <div class="mw-heading mw-heading3"><h3 id="Fabrication">Fabrication</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=10" title="Edit section: Fabrication"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha 21164 contains 9.3 million transistors on a <a href="/wiki/Die_(integrated_circuit)" title="Die (integrated circuit)">die</a> measuring 16.5 by 18.1 mm (299 mm<sup>2</sup>), which was close to the maximum limits of the process. The die was <a href="/wiki/Semiconductor_device_fabrication" title="Semiconductor device fabrication">fabricated</a> in Digital's fifth-generation <a href="/wiki/CMOS" title="CMOS">complementary metal–oxide–semiconductor</a> (CMOS) process, CMOS-5, a 0.50 μm process with four levels of <a href="/wiki/Aluminium_interconnect" class="mw-redirect" title="Aluminium interconnect">aluminium interconnect</a>.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> The 21164 used a 3.3-<a href="/wiki/Volt" title="Volt">volt</a> (V) power supply. It dissipated 46 W at 266 MHz, 51 W at 300 MHz, 56 W at 333 MHz. </p> <div class="mw-heading mw-heading3"><h3 id="Package">Package</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=11" title="Edit section: Package"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Alpha 21164 is packaged in a 499-pin ceramic interstitial <a href="/wiki/Pin_grid_array" title="Pin grid array">pin grid array</a> (IPGA) measuring 57.40 by 57.40 mm. The package had a <a href="/wiki/Heat_spreader" title="Heat spreader">heat spreader</a> with two studs to which the <a href="/wiki/Heat_sink" title="Heat sink">heat sink</a> was bolted. </p> <div class="mw-heading mw-heading2"><h2 id="Derivatives">Derivatives</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=12" title="Edit section: Derivatives"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Alpha_21164_(EV56)"><span id="Alpha_21164_.28EV56.29"></span>Alpha 21164 (EV56)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=13" title="Edit section: Alpha 21164 (EV56)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:DEC_Alpha_21164.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2f/DEC_Alpha_21164.jpg/220px-DEC_Alpha_21164.jpg" decoding="async" width="220" height="219" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2f/DEC_Alpha_21164.jpg/330px-DEC_Alpha_21164.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2f/DEC_Alpha_21164.jpg/440px-DEC_Alpha_21164.jpg 2x" data-file-width="1368" data-file-height="1359" /></a><figcaption>A 500 MHz Alpha 21164 (EV56) microprocessor</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Alpha_EV56_die.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/42/Alpha_EV56_die.JPG/220px-Alpha_EV56_die.JPG" decoding="async" width="220" height="219" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/42/Alpha_EV56_die.JPG/330px-Alpha_EV56_die.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/42/Alpha_EV56_die.JPG/440px-Alpha_EV56_die.JPG 2x" data-file-width="3279" data-file-height="3259" /></a><figcaption>Samsung Alpha 21164 (EV56) die shot</figcaption></figure> <p>The Alpha 21164 was the basis of a further development code-named <b>EV56</b>. It was introduced as the Alpha 21164, but was originally known as the <b>Alpha 21164A</b>. It operated at clock frequencies of 366, 433, 500, 533, 566, 600 and 666 MHz.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><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> </p> <div class="mw-heading mw-heading4"><h4 id="History_2">History</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=14" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>It was first described in October 1995 at the Microprocessor Forum. On 13 November 1995, Digital announced that samples would ship later in the month. The first version, operating at 366 MHz, was introduced in 1996. On 8 July 1996, Digital announced that a 433 MHz version was available and a 500 MHz version was sampling with volume quantities due in September 1996. The 433 MHz version was priced at $1,492 per unit in quantities of 1,000. The 600 MHz version was introduced on 31 March 1997, shipping in volume quantities. <a href="/wiki/Samsung_Electronics" title="Samsung Electronics">Samsung Electronics</a> signed a deal with Digital in June 1996 to <a href="/wiki/Second_source" title="Second source">second source</a> the Alpha 21164A and the company was the only one to fabricate the 666 MHz model. 366 to 500 MHz samples were introduced on 11 November 1996 with volume availability in 1997. The Alpha 21164A was fabricated at Digital's <a href="/wiki/Hudson,_Massachusetts" title="Hudson, Massachusetts">Hudson, Massachusetts</a> and Samsung's Kihueng, South Korea <a href="/wiki/Fabrication_plant" class="mw-redirect" title="Fabrication plant">fabrication plants</a>. </p><p>Users of the Alpha 21164A included Cray Research, Digital, <a href="/wiki/NetApp" title="NetApp">Network Appliance</a> (now NetApp), and DeskStation. Cray Research used 450, 600 and 675 MHz Alpha 21164As in later models of their <a href="/wiki/Cray_T3E" title="Cray T3E">T3E</a> supercomputer. Digital used the Alpha 21164A operating at various clock frequencies in their <a href="/wiki/AlphaServer" title="AlphaServer">AlphaServers</a>, <a href="/wiki/AlphaStation" title="AlphaStation">AlphaStations</a>, Celebris XL workstations and <a href="/wiki/Digital_Personal_Workstation" title="Digital Personal Workstation">Digital Personal Workstations</a>. NetApp used 400, 500 and 600 MHz Alpha 21164As in their <a href="/wiki/NetApp_filer" class="mw-redirect" title="NetApp filer">storage systems</a>. DeskStation used the Alpha 21164A in their Raptor Reflex workstations. </p> <div class="mw-heading mw-heading4"><h4 id="Description_2">Description</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=15" title="Edit section: Description"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The most notable change was the inclusion of Byte Word Extensions (BWX), an extension to the Alpha Architecture designed to improve byte and word accesses. These instructions are executed by the multiply pipeline. The Alpha 21164A contained 9.66 million transistors on a die measuring 14.4 mm by 14.5 mm, for a die area of 209 mm<sup>2</sup>.<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> Digital fabricated the die in their sixth generation CMOS process, CMOS-6, a 0.35 μm process with four layers of interconnect. Samsung fabricated the die in their 0.35 μm process with four layers of interconnect based on a 0.3 μm process they developed in early 1996. The Alpha 21164A used a 3.3 V power supply, dissipating 31.0 W at 366 MHz, 36.0 W at 433 MHz, 41.0 W at 500 MHz, 43.5 W at 533 MHz and 48.5 W at 600 MHz. </p> <div class="mw-heading mw-heading3"><h3 id="Alpha_21164PC_(PCA56)"><span id="Alpha_21164PC_.28PCA56.29"></span>Alpha 21164PC (PCA56)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=16" title="Edit section: Alpha 21164PC (PCA56)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>Alpha 21164PC</b>, also known as the <b>PCA56</b>, is a low-cost version of the Alpha 21164A introduced on 17 March 1997. The microprocessor was jointly developed by Digital and <a href="/wiki/Mitsubishi_Electric" title="Mitsubishi Electric">Mitsubishi Electric Corporation</a>, and both companies fabricated the design. Mitsubishi later suspended the joint development agreement for future Alpha microprocessors with Digital in early 1998 and ceased to fabricate the Alpha 21164PC in mid-1998, exited the Alpha market because the economic conditions in the company's markets.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><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> </p><p>The Alpha 21164PC operated at clock frequencies of 400, 466 and 533 MHz. Major changes are the omission of the S-cache, a larger I-cache, and the inclusion of Motion Video Instructions (MVI), an extension to the Alpha Architecture which introduced <a href="/wiki/SIMD" class="mw-redirect" title="SIMD">single instruction multiple data</a> (SIMD) instructions for improving the performance of <a href="/wiki/MPEG" class="mw-redirect" title="MPEG">MPEG</a> encoding. The S-cache was removed to reduce the transistor count, which reduced the die size and in turn, cost. The I-cache was doubled in capacity to 16 KB from 8 KB to compensate for the lack of S-cache, as the Alpha 21164 relied on the S-cache to complement the I-cache in order to provide enough bandwidth to achieve adequate performance. The amount of B-cache was limited to 512 KB to 4 MB, with 1 and 2 MB capacities also supported. The microprocessor uses a 43-bit virtual address and 33-bit physical address. </p><p>The Alpha 21164PC contained 3.5 million transistors on a die measuring 8.65 by 16.28 mm, for a die area of 141 mm<sup>2</sup>. Digital fabricated the die in the same process as the Alpha 21164, CMOS-5. The Alpha 21164PC was packaged in 413-pin IPGA measuring 49.78 by 49.78 mm. It used a 3.3 V power supply, dissipating 26.5 W at 400 MHz, 30.5 W at 466 MHz and 35.0 W at 533 MHz. </p><p>The Alpha 21164PC was used by Digital in their AlphaPC 164SX motherboard. </p> <div class="mw-heading mw-heading3"><h3 id="Alpha_21164PC_(PCA57)"><span id="Alpha_21164PC_.28PCA57.29"></span>Alpha 21164PC (PCA57)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=17" title="Edit section: Alpha 21164PC (PCA57)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A derivative of the PCA56, the <b>PCA57</b> was designed and fabricated by <a href="/wiki/Samsung_Electronics" title="Samsung Electronics">Samsung Electronics</a> in a 0.28 μm CMOS process. The PCA57 was introduced in late 1998 and operated at clock frequencies of 533, 600 and 666 MHz. Improvements to the PCA56 microarchitecture included doubled I-cache and D-cache capacities: 32 KB and 16 KB respectively. The PCA57 contained 5.7 million transistors on a die measuring 6.7 mm by 15 mm, for a die area of 101 mm<sup>2</sup>. It operated on a 2.5 V power supply and dissipated 18 W at 533 MHz, 20 W at 600 MHz and 23 W at 666 MHz. </p><p>The PCA57 was used by Digital in its AlphaPC 164RX motherboard. </p> <div class="mw-heading mw-heading2"><h2 id="Chipsets">Chipsets</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=18" title="Edit section: Chipsets"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Digital and VLSI Technology developed chipsets for the 21164 and its derivatives. Digital also developed custom <a href="/wiki/Application-specific_integrated_circuit" title="Application-specific integrated circuit">application-specific integrated circuit</a> (ASICs) for use in the high-end models of their <a href="/wiki/AlphaServer" title="AlphaServer">AlphaServer</a> family such as the AlphaServer 8200 and 8400. </p> <div class="mw-heading mw-heading3"><h3 id="21171">21171</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=19" title="Edit section: 21171"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 21171, also known as Alcor, was the first chipset for the 21164, introduced in January 1995 alongside the microprocessor it supports. It was developed and fabricated by Digital. The 21171 is an upgraded <a href="/wiki/Alpha_21064#Chipsets" title="Alpha 21064">DECchip 21071</a> modified to support the new system bus protocol the 21164 uses. It consisted of a control chip that contained the <a href="/wiki/Memory_controller" title="Memory controller">memory</a> and <a href="/w/index.php?title=PCI_controller&action=edit&redlink=1" class="new" title="PCI controller (page does not exist)">PCI controllers</a>, and four data slice chips that interfaced the 256-bit <a href="/wiki/Memory_bus" class="mw-redirect" title="Memory bus">memory bus</a> and <a href="/wiki/Conventional_PCI" class="mw-redirect" title="Conventional PCI">PCI</a> bus to the system bus. The 21171 provides a 64-bit wide PCI bus that runs at 33 MHz. </p> <div class="mw-heading mw-heading3"><h3 id="21172">21172</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=20" title="Edit section: 21172"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 21172, also known as Alcor2, was an updated 21171 that supported the 21164A. </p> <div class="mw-heading mw-heading3"><h3 id="Pyxis">Pyxis</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=21" title="Edit section: Pyxis"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Pyxis chipset, also known as the 21174, supported the 21164A and 21164PC microprocessors. Unlike previous chipsets, it was designed for low-cost systems. As a result, it was a single-chip design packaged in a 474-contact <a href="/wiki/Ceramic_ball_grid_array" class="mw-redirect" title="Ceramic ball grid array">ceramic ball grid array</a> (CBGA) instead of multiple packages.<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> It was subsequently used in cost-sensitive applications such as entry-level workstations (<a href="/wiki/Digital_Personal_Workstation" title="Digital Personal Workstation">Digital Personal Workstation a-Series</a>) and motherboards such as the AlphaPC 164LX and 164SX. When it was introduced, the 21174 was priced at US$142 in quantities of 1,000.<sup id="cite_ref-MPR-1997-03-31_15-0" class="reference"><a href="#cite_note-MPR-1997-03-31-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p>The 21174 contains a memory controller and PCI controller. The memory controller supported up to 512 MB of <a href="/wiki/Synchronous_dynamic_random_access_memory" class="mw-redirect" title="Synchronous dynamic random access memory">synchronous dynamic random access memory</a> (SDRAM) and accesses it via a 128-bit <a href="/wiki/Memory_bus" class="mw-redirect" title="Memory bus">memory bus</a>. The memory can be either ECC or parity protected. The PCI controller provided a <a href="/wiki/Conventional_PCI" class="mw-redirect" title="Conventional PCI">PCI</a> or <a href="/wiki/PCI-X" title="PCI-X">PCI-X</a> bus. </p> <div class="mw-heading mw-heading3"><h3 id="Polaris">Polaris</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=22" title="Edit section: Polaris"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Polaris is a system controller developed by <a href="/wiki/VLSI_Technology" title="VLSI Technology">VLSI Technology</a> for personal computers that supports the 21164A and 21164PC microprocessors. Polaris was announced on 16 June 1997.<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> It supports up to 768 MB of EDO DRAM or up to 512 MB of SDRAM. The memory is accessed via a 128-bit bus. It provides a 32-bit, 33 MHz <a href="/wiki/Conventional_PCI" class="mw-redirect" title="Conventional PCI">PCI</a> bus for I/O. </p><p>Users of Polaris included Digital, for its AlphaPC 164RX motherboard. </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=Alpha_21164&action=edit&section=23" 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"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a href="#MPR_1996-07-08">Gwennap 1996</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">Bowhill et al., <a href="#DTJ_1995_1">"Circuit implementation of a 300-MHz 64-bit second-generation CMOS Alpha CPU"</a>, p. 124.</span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">Bowhill et al., <a href="#DTJ_1995_1">"Circuit implementation of a 300-MHz 64-bit second-generation CMOS Alpha CPU"</a>, p. 111.</span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text">Gwennap, <a href="#MPR_1994-09-12">"Digital Leads the Pack with 21164"</a>, p. 1.</span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">Gwennap, <a href="#MPR_1994-09-12">"Digital Leads the Pack with 21164"</a>, pp. 1–2.</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text">Gwennap, <a href="#MPR_1994-09-12">"Digital Leads the Pack with 21164".</a></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text">Bowhill, et al., <a href="#DTJ_1995_1">"Circuit implementation of a 300-MHz 64-bit second-generation CMOS Alpha CPU"</a>, pp. 100–101.</span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><i>Alpha 21164 Microprocessor Data Sheet, August 1998</i>, p. 113.</span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><i>Digital Semiconductor 21164 Alpha Microprocessor Product Brief, 31 March 1997</i>, p. 2.</span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><a href="#CCL-Forum">"CCL: DEC Alpha 566 vs. 600 MHz"</a></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text">Bouchard, <a href="#HC">"Design objectives of the 0.35 μm Alpha 21164 Microprocessor"</a>, p. 3, 5.</span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text">Foremski, <a href="#EW_1998-02-10">"Mitsubishi steps back from Alpha"</a>.</span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text">Foremski, <a href="#EW_1998-07-10">"Mitsubishi Electric stops Alpha microprocessor manufacture"</a>.</span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><a href="#DTJ-1997">Schumann 1997</a></span> </li> <li id="cite_note-MPR-1997-03-31-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-MPR-1997-03-31_15-0">^</a></b></span> <span class="reference-text"><a href="#MPR-1997-03-31">Gwennap 1997</a></span> </li> <li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><a href="#VLSI-1997">VLSI Technology 1997</a></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=Alpha_21164&action=edit&section=24" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><cite id="HC">Bouchard, Gregg. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110723210647/http://www.hotchips.org/archives/hc8/2_Mon/HC8.S1/HC8.1.2.pdf">"Design objectives of the 0.35 μm Alpha 21164 Microprocessor"</a>. IEEE Hot Chips Symposium, August 1996, IEEE Computer Society.</cite></li> <li><cite id="DTJ_1995_1">Bowhill, William J. et al. (1995). "Circuit Implementation of a 300-MHz 64-bit Second-generation CMOS Alpha CPU". <i>Digital Technical Journal</i>, Volume 7, Number 1, pp. 100–118.</cite></li> <li><cite id="DTJ_1995_2">Edmondson, John H. et al. (1995). "Internal Organization of the Alpha 21164, a 300-MHz 64-bit Quad-issue CMOS RISC Microprocessor". <i>Digital Technical Journal</i>, Volume 7, Number 1, 1995. pp. 119–135.</cite></li> <li>Edmondson, John H. et al. (1995). "Superscalar Instruction Execution in the 21164 Alpha Microprocessor". <i><a href="/wiki/IEEE_Micro" title="IEEE Micro">IEEE Micro</a></i>. pp. 33–43.</li> <li><cite id="EW_1998-02-10">Foremski, Tom (10 February 1998). <a rel="nofollow" class="external text" href="https://archive.today/20130102134010/http://www.electronicsweekly.com/Articles/1998/02/10/6285/mitsubishi-steps-back-from-alpha.htm">"Mitsubishi steps back from Alpha"</a>. <i>Electronics Weekly</i>.</cite></li> <li><cite id="EW_1998-07-10">Foremski, Tom (10 July 1998). <a rel="nofollow" class="external text" href="http://www.electronicsweekly.com/Articles/1998/07/10/8039/mitsubishi-electric-stops-alpha-microprocessor-manufacture.htm">"Mitsubishi Electric stops Alpha microprocessor manufacture"</a>. <i>Electronics Weekly</i>.</cite></li> <li><cite id="MPR_1994-09-12">Gwennap, Linley (12 September 1994). "Digital Leads the Pack with 21164". <i><a href="/wiki/Microprocessor_Report" title="Microprocessor Report">Microprocessor Report</a></i>, Volume 8, Number 12.</cite></li> <li><cite id="MPR_1996-07-08">Gwennap, Linley (8 July 1996). "Digital's 21164 Reaches 500 MHz". <i><a href="/wiki/Microprocessor_Report" title="Microprocessor Report">Microprocessor Report</a></i>, Volume 10, Number 9.</cite></li> <li><cite id="MPR-1997-03-31">Gwennap, Linley (31 March 1997). "Digital's 21164PC Aimed at PC Market". <i><a href="/wiki/Microprocessor_Report" title="Microprocessor Report">Microprocessor Report</a></i>, Volume 11, Number 4.</cite></li> <li>Ryan, Bob (October 1994). "Alpha Rides High". <i><a href="/wiki/Byte_(magazine)" title="Byte (magazine)">Byte</a></i>.</li> <li>Samsung Semiconductor, Inc. (11 November 1996). "<a rel="nofollow" class="external text" href="http://www.thefreelibrary.com/Samsung+Introduces+500MHz+Alpha+21164+Microprocessor%3B+First+product...-a018845426">Samsung Introduces 500MHz Alpha 21164 Microprocessor; First product resulting from the Digital/Samsung licensing agreement to begin mass production by Q2 1997</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20121011124856/http://www.thefreelibrary.com/Samsung+Introduces+500MHz+Alpha+21164+Microprocessor%3B+First+product...-a018845426">Archived</a> 2012-10-11 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>". Press release.</li> <li><cite id="DTJ-1997">Schumann, Reinhard C. (1997). <a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/dtj/vol9num2/vol9num2art5.pdf">"Design of the 21174 memory controller for Digital Personal Workstations"</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080906001145/http://www.hpl.hp.com/hpjournal/dtj/vol9num2/vol9num2art5.pdf">Archived</a> 2008-09-06 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>. <i>Digital Technical Journal</i> <b>9</b> (2): 57–70.</cite></li> <li><cite id="VLSI-1997">VLSI Technology (16 June 1997). "Polaris, VLSI's New Alpha System Controller, Breaks the Gigabyte/Second Memory Transfer Barrier. End-Users Gain Full Performance on Alpha Systems". Press release.</cite></li> <li><cite id="CCL-Forum">CCL Forums (25 March 1998). <a rel="nofollow" class="external text" href="http://www.ccl.net/chemistry/resources/messages/1998/03/30.014-dir/index.html">"DEC Alpha 566 vs. 600 MHz"</a></cite></li></ul> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_21164&action=edit&section=25" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Bannon, P., Saito, Y. (1997). <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=584665">"The Alpha 21164PC microprocessor"</a>. <i>Proceedings of Compcon '97</i>, pp. 20–27.</li> <li>Bhandarkar, Dileep P. (1995). <i>Alpha Architecture and Implementations</i>. Digital Press.</li> <li>Carlson, D. et al. (1998). "A 667 MHz RISC microprocessor containing a 6.0 ns 64 b integer multiplier". <i>ISSCC Digest of Technical Papers</i>, pp. 294–295.</li> <li>Carlson, D.A.; Castelino, R.W.; Mueller, R.O. (November 1997). <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=641681">"Multimedia extensions for a 550-MHz RISC microprocessor"</a>. <i>IEEE Journal of Solid-State Circuits</i> <b>32</b> (11): pp. 1618–1624.</li> <li>Jain, A.K. et al. (1997). "1.38 cm<sup>2</sup> 550 MHz microprocessor with multimedia extensions". <i>ISSCC Digest of Technical Papers</i>, pp. 174–175, 451.</li> <li>Gronowski, Paul E. et al. (May 1998). "High-performance microprocessor design". <i>IEEE Journal of Solid-State Circuits</i> <b>33</b> (5): pp. 676–686.</li> <li>Kobayashi, S. et al. (1997). <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=614758">"A 550 MHz Alpha microprocessor targeted at PC applications"</a>. <i>Proceedings of the 1997 International Symposium on VLSI Technology, Systems, and Applications</i>, pp. 203–207.</li></ul> <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=Alpha_21164&action=edit&section=26" 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="https://m.youtube.com/watch?v=OHupqMbLj1g">An Overview of the Alpha AXP 21164 Micro-Architecture, lecture by John Edmonson</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist 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.navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Digital_Equipment_Corporation" title="Template:Digital Equipment Corporation"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Digital_Equipment_Corporation" title="Template talk:Digital Equipment Corporation"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Digital_Equipment_Corporation" title="Special:EditPage/Template:Digital Equipment Corporation"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Digital_Equipment_Corporation805" style="font-size:114%;margin:0 4em"><a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a></div></th></tr><tr><th scope="row" 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/110px-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/165px-Digital_Equipment_Corporation_1993_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/90/Digital_Equipment_Corporation_1993_logo.svg/220px-Digital_Equipment_Corporation_1993_logo.svg.png 2x" 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 href="/wiki/DEC_Alpha" title="DEC Alpha">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 class="mw-selflink selflink">Alpha 21164</a> (<a class="mw-selflink-fragment" href="#Alpha_21164PC_(PCA56)">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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