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<!DOCTYPE HTML> <html lang="en"> <head> <meta charset="utf-8"> <style id="antiClickjack">body{display:none !important;}</style> <script> if (self === top) { var antiClickjack = document.getElementById("antiClickjack"); antiClickjack.parentNode.removeChild(antiClickjack); } else { top.location = self.location; } </script> <meta name=viewport content="width=device-width, initial-scale=1"> <link rel="shortcut icon" href="/img/favicon.ico" type="image/x-icon"> <link rel="apple-touch-icon" href="/img/apple-touch-icon.png"> <link rel="stylesheet" href="/main.css" type="text/css">  <link rel="canonical" href="https://www.helpwithpcs.com/jargon/ssd-solid-state-drive.htm"> <meta name="description" content="An overview of SSD technology, including the advantages and disadvantages of these devices compared to electromechanical hard disk drives."> <title>What does SSD mean and what is it?</title> </head> <body> <div id="top_outer"> <div id="header"> <div id="header_inn"> <div id="logo"><a href="/"><img src="/img/help-with-pcs.png" width="318" height="40" alt="Help with PCs" title="Click for our homepage"></a></div> <div id="hdr_srch"> </div> </div> </div> <div id="nav_outer"> <ul class="nav_mn"> <li class="nav"><a href="/hardware/" class="nav">HARDWARE</a></li> <li class="nav"><a href="/software/" class="nav">SOFTWARE</a></li> <li class="nav"><a href="/internet/" class="nav">INTERNET</a></li> <li class="nav"><a href="/upgrading/" class="nav">PC UPGRADING</a></li> <li class="nav"><a href="/maintenance/" class="nav">PC MAINTENANCE</a></li> <li class="nav"><a href="/jargon/" class="nav2">DICTIONARY</a></li> <li class="nav"><a href="/gaming/" class="nav">GAMING</a></li> </ul> </div> </div> <div id="wrapper"> <div class="c_container"> <div itemscope itemtype="http://schema.org/TechArticle"> <h1 itemprop="name">What does SSD mean and what is it?</h1> <div class="cnt_hdr_box"> <div class="cnt_hdr_img"><img src="/jargon/img/ssd-solid-state-drive.png" width="180" height="140" alt="solid-state drive" title="solid-state drive" class="mn_img"></div> <div class="cnt_hdr_txt"> <span class="emphlge">SSD - solid-state drive</span> <br> The term SSD (solid-state drive) refers to a non-mechanical storage device which is typically faster than traditional disk-based data storage. Solid-state drives use NAND-based flash memory or DRAM to hold electrical charges which represent the binary digits forming the data. </div> </div> <div class="gads_hdr"> <div class="cnt_ad_undhdr_hdr">advertisement</div> <div class="cnt_ad_undhdr_ad"> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>  <ins class="adsbygoogle gads_hdr_res" data-ad-client="ca-pub-7821244969182905" data-ad-slot="2064534968" data-ad-format="auto"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> <hr></div> <div class="cnt_padd"> <h2>Advantages of SSD over electromechanical disk storage</h2> <h3>Speed and performance</h3> SSDs have much faster access rates than electromechanical disk drives (<a href="/hardware/hard-drive-basics.php">HDDs</a>) as they do not depend on the placement of a read/write head on a magnetic platter to access the requested data. <br><br> The data transfer performance of a mechanical drive is limited by its spindle speed, SSDs have sequential read speeds ranging from around 560MB/s (<a href="/jargon/megabyte.htm">megabyte</a> per second) to over 3,500MB/s depending on the interface, compared to standard HDDs which have sequential read speeds of up to around 210MB/s (SATA 6 Gb/s) on a 7,200 RPM HDD. <h3>Shock resistance</h3> SSDs are much more resistant to shocks than their magnetic disk counterparts as they have no moving parts. A typical electromechanical drive has a shock resistance of 55g (0.12lbs) while operating and 350g (0.77lbs) while not operating, whereas a typical SSD device can tolerate up to 1,500g (3.31lbs) of shock regardless of whether it is operating or not. Also, many models actually power down if a shock is detected. <h3>Power efficient, silent and vibration free</h3> Because SSDs have no moving parts they are not only silent and have no vibration, they also require less power than their mechanical cousins, making them ideal for portable devices such as laptops where battery life is important. <h2>Disadvantages of SSD devices</h2> <h3>Cost and capacity</h3> Currently, SSD devices have a larger cost-per-megabyte than electromechanical drives but this will balance out in the future as the devices and the technology mature. The limited storage capacity can be an issue, but again, storage capacities continue to grow at a healthy rate. <h3>Data retention</h3> SSD devices do not store the data permanently, they require power in order to maintain the electrical charges. The length of time an SSD can maintain data without power varies greatly between client devices (<i>those designed for the consumer market</i>) and enterprise devices (<i>those developed for business/heavy use</i>). The operating temperature and the storage temperature also have a dramatic effect on the length of time data can be stored. <br><br> Figures published by Intel and cited in the <a href="https://www.jedec.org/sites/default/files/Alvin_Cox%20%5bCompatibility%20Mode%5d_0.pdf" target="jedec">JEDEC SSD specification</a> <span class="lnk_nw">(link opens in new window)</span> show that a typical client (consumer) device operated at 40°C (104°F) will hold its data for two years if stored at a temperature of 25°C (75°F). That same device would only hold its data for one year if it was stored at just 5°C higher (30°C (86°F)), so care should be taken when storing SSD devices for long periods of time. As temperature has such an effect on SSD devices, it is also wise to keep them out of direct sunlight. <br><br> <strong>note:</strong> The figures quoted above relate to an SSD device which has outlived its endurance rating (lifespan). Also, this does not mean that the SSD device will suddenly be empty after that period of time but it could affect the integrity of the data stored as time passes. <h2>What is MTTF, MTBF and TBW?</h2> SSD devices are advertised as having a <b><em>life expectancy</em></b> and an <b><em>endurance</em></b> rating. <br> <h3>MTTF (Mean Time To Failure) / MTBF (Mean Time Between Failure)</h3> These two terms are used interchangeably by manufacturers when listing <em>life expectancy</em> of SSD devices. Both terms relate to the same specification, except MTTF (Mean Time To Failure) describes <em>non-repairable</em> devices/systems, while MTBF (Mean Time Between Failure) describes <em>repairable</em> devices/systems. Whether SSD devices are actually repairable is another topic. <br><br> MTTF/MTBF specifications are listed in hours with a typical value of around 1,500,000 (1.5M) hours for SSDs. This states that under optimal conditions (within their useful life) the device should function for over 170 years. Not sure who of us will still be around to confirm that figure, and it is probably a specification aimed more at marketing, than reality. In reality, wear-out modes, such as TBW below, would limit its life much earlier than its MTTF/MTBF figure. <h3>TBW (Total Bytes Written)</h3> This specification is probably more important and more realistic than the MTTF figures, which is possibly why it is sometimes used to define the terms of the manufacturer's warranty. It specifies how many, on average, bytes can be written to the device before it fails. <br><br> TBW figures are typically given in <a href="/jargon/terabyte.htm">terabytes (TB)</a>. For example, Samsung<sup>®</sup> advertise their 1TB 850 Evo SSD as having a TBW maximum of 150TB (TeraBytes), meaning you should be able to write 150TB of data to the device before it fails. Some manufacturers, including Samsung<sup>®</sup>, also state a maximum time period alongside their TBW in their warranty terms. <h2>SSHD - solid-state hybrid drive</h2> An SSHD, or simply "hybrid drive" includes both a traditional electromechanical disk drive along with an SSD which is used for caching frequently accessed data. Depending on the configuration and/or device, either the device's firmware, or the operating system will determine which data to move from the mechanical disk to the SSD drive for faster access. <br><br> SSHDs offer a nice balance of high storage capacity with the speed of SSD, although any performance benefits are dependent on the size of the SSD and the success rate of the caching. <br><br> A true solid-state hybrid drive has both the mechanical and SSD within the same device. However, the setup can be replicated in a desktop PC or laptop which has both a standard HDD and an SSD installed. To take advantage of this configuration install the operating system and/or store your most frequently used data on the SSD, this will improve the day-to-day performance of your system. </div> <hr> </div> <div class="gads_bott"> <div class="cnt_ad_bt_hdr_bott">advertisement</div> <div class="cnt_bt_ad_bott"> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script> <ins class="adsbygoogle gads_bt_res" data-ad-client="ca-pub-7821244969182905" data-ad-slot="3563024169" data-ad-format="auto"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> <hr></div> </div> <div class="rh_col"> <div class="cnt_ad_bt_hdr">advertisement</div> <div class="cnt_bt_ad"> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script> <ins class="adsbygoogle" style="display:block" data-ad-client="ca-pub-7821244969182905" data-ad-slot="7470663368" data-ad-format="auto"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div></div> </div> <hr class="social"> <div class="sco"> <div class="social"><a href="https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fwww.helpwithpcs.com%2Fjargon%2Fssd-solid-state-drive.htm" rel="nofollow" target="facebook"><img src="/img/social/facebook.png" width="42" height="42" alt="fb" class="social"></a></div> <div class="social"><a href="http://twitter.com/share?url=https%3A%2F%2Fwww.helpwithpcs.com%2Fjargon%2Fssd-solid-state-drive.htm" rel="nofollow" target="twitter"><img src="/img/social/twitter.png" width="42" height="42" alt="tw" class="social"></a></div> <div class="social"><a href="http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fwww.helpwithpcs.com%2Fjargon%2Fssd-solid-state-drive.htm" rel="nofollow" target="linkedin"><img src="/img/social/linkedin.png" width="42" height="42" alt="ld" class="social"></a></div> <div class="social"><a href="http://www.reddit.com/submit?url=https%3A%2F%2Fwww.helpwithpcs.com%2Fjargon%2Fssd-solid-state-drive.htm" rel="nofollow" target="reddit"><img src="/img/social/reddit.png" width="42" height="42" alt="rt" class="social"></a></div> <div class="social"><a href="http://www.digg.com/submit?url=https%3A%2F%2Fwww.helpwithpcs.com%2Fjargon%2Fssd-solid-state-drive.htm" rel="nofollow" target="digg"><img src="/img/social/digg.png" width="42" height="42" alt="dg" class="social"></a></div> <div class="social"><a href="https://plusone.google.com/_/+1/confirm?hl=en&url=https%3A%2F%2Fwww.helpwithpcs.com%2Fjargon%2Fssd-solid-state-drive.htm" rel="nofollow" target="google_plus"><img src="/img/social/google_plus.png" width="42" height="42" alt="gp" class="social"></a></div> </div> <hr class="social"><div id="ftr_outer"> <div id="ftr_inner"> <hr class="wh"> <div class="ftr_lnks"><a href="https://www.helpwithpcs.com/advert-form.php" class="wh">Advertising</a></div> <div class="ftr_lnks"><a href="https://www.helpwithpcs.com/contact-us.php" class="wh">Contact us</a></div> <div class="ftr_lnks"><a href="https://www.helpwithpcs.com/copyright-information.html" class="wh">Copyright</a></div> <div class="ftr_lnks"><a href="https://www.helpwithpcs.com/disclaimer.html" class="wh">Disclaimer</a></div> <div class="ftr_lnks"><a href="https://www.helpwithpcs.com/privacy-policy.html" class="wh">Privacy policy</a></div> <div class="fix"></div> <hr class="wh"> <div class="ftr_lnks">© Copyright 2001-2024 HelpWithPCs.com</div> <div class="fix"></div> <hr class="wh"> </div> </div> <script> var _paq = _paq || []; _paq.push(['trackPageView']); _paq.push(['enableLinkTracking']); (function() { var u="//www.wdgsystems.co.uk/analytics_pk/"; _paq.push(['setTrackerUrl', u+'piwik.php']); _paq.push(['setSiteId', '3']); var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0]; g.type='text/javascript'; g.async=true; g.defer=true; g.src=u+'piwik.js'; s.parentNode.insertBefore(g,s); })(); </script> </body> </html>