Editing Computer cooling (section)

===Liquid cooling===
{{further|topic=water cooling|Water cooling#Computer usage}}

[[File:Deepcool cooler.png|thumb|right|An all-in-one (AIO) cooling unit, installed in a case]]
[[File:PC watercooling T-Line-2009-12-03.jpg|thumb|left|[[Do it yourself|DIY]] water cooling setup showing a 12&nbsp;V pump, CPU [[waterblock]] and the typical application of a [[T-Line]]]]
[[File:Liquid cooling schematic.png|thumb|left|Schematic of a regular liquid cooling setup for PCs]]

Liquid cooling is a highly effective method of removing excess heat, with the most common [[Coolant|heat transfer fluid]] in desktop PCs being (distilled) water. The advantages of water cooling over [[air cooling]] include water's higher [[specific heat capacity]] and [[thermal conductivity]].

The principle used in a typical (active) liquid cooling system for computers is identical to that used in an automobile's [[internal combustion engine]], with the water being circulated by a water pump through a water block mounted on the CPU (and sometimes additional components as GPU and northbridge)<ref name="auto">{{cite web|url=http://computer.howstuffworks.com/liquid-cooled-pc2.htm|title=How Liquid-cooled PCs Work|date=24 August 2006|access-date=24 July 2014|archive-url=https://web.archive.org/web/20140721124907/http://computer.howstuffworks.com/liquid-cooled-pc2.htm|archive-date=21 July 2014|url-status=live}}</ref> and out to a [[heat exchanger]], typically a [[radiator]]. The radiator is itself usually cooled additionally by means of a [[Computer fan|fan]].<ref name="auto"/> Besides a fan, it could possibly also be cooled by other means, such as a Peltier cooler (although Peltier elements are most commonly placed directly on top of the hardware to be cooled, and the coolant is used to conduct the heat away from the hot side of the Peltier element).<ref>{{cite web|url=http://computer.howstuffworks.com/liquid-cooled-pc5.htm|title=How Liquid-cooled PCs Work|date=24 August 2006|access-date=25 July 2014|archive-url=https://web.archive.org/web/20140729200304/http://computer.howstuffworks.com/liquid-cooled-pc5.htm|archive-date=29 July 2014|url-status=live}}</ref><ref>{{cite web|url=http://www.tomshardware.co.uk/forum/282844-29-peltier-water-cooling|title=TEC/Peltier CPU Chilled Water Cooling – Overclocking|website=Tom's Hardware|access-date=24 July 2014|archive-url=https://web.archive.org/web/20140808074239/http://www.tomshardware.co.uk/forum/282844-29-peltier-water-cooling|archive-date=8 August 2014|url-status=live}}</ref> A coolant reservoir is often also connected to the system.<ref>{{cite web|url=http://www.techradar.com/news/computing-components/upgrades/pc-water-cooling-guide-all-you-need-to-know-952521|title=PC water cooling guide: all you need to know|date=8 May 2011|access-date=24 July 2014|archive-url=https://web.archive.org/web/20140728040240/http://www.techradar.com/news/computing-components/upgrades/pc-water-cooling-guide-all-you-need-to-know-952521|archive-date=28 July 2014|url-status=live}}</ref>

Besides active liquid cooling systems, passive liquid cooling systems are also sometimes used.<ref>{{cite web|url=http://www.techradar.com/news/computing-components/upgrades/pc-water-cooling-guide-all-you-need-to-know-952521/2#articleContent|title=PC water cooling guide: all you need to know|date=8 May 2011|access-date=25 July 2014|archive-url=https://web.archive.org/web/20140728102802/http://www.techradar.com/news/computing-components/upgrades/pc-water-cooling-guide-all-you-need-to-know-952521/2#articleContent|archive-date=28 July 2014|url-status=live}}</ref><ref>{{cite web|url=http://www.tomshardware.com/news/silverstone-td04-pumpless-liquid-cooling,27023.html|title=SilverStone Reveals Pumpless Liquid Cooling System|date=10 June 2014}}</ref><ref>{{cite web|url=http://www.overclockers.com/cpu-vapor-cooling-thermosyphon/|title=CPU Vapor Cooling Thermosyphon – Overclockers|date=4 November 2005|access-date=25 July 2014|archive-url=https://web.archive.org/web/20140727122319/http://www.overclockers.com/cpu-vapor-cooling-thermosyphon/|archive-date=27 July 2014|url-status=live}}</ref><ref>{{cite web|url=http://www.overclock.net/t/607208/water-cooling-without-pump/30|title=Water Cooling Without Pump – Page 4 – Overclock.net – An Overclocking Community|website=overclock.net|date=26 May 2011 |access-date=25 July 2014|archive-url=https://web.archive.org/web/20140812174650/http://www.overclock.net/t/607208/water-cooling-without-pump/30|archive-date=12 August 2014|url-status=live}}</ref><ref>{{cite web|url=http://www.xtremesystems.org/forums/showthread.php?218039-passive-pumpless-watercooling|title=passive pumpless watercooling|website=xtremesystems.org|access-date=25 July 2014|archive-url=https://web.archive.org/web/20140811130340/http://www.xtremesystems.org/forums/showthread.php?218039-passive-pumpless-watercooling|archive-date=11 August 2014|url-status=live}}</ref> These systems often leave out a fan or a water pump, theoretically increasing their reliability and making them quieter than active systems. The downsides of these systems are that they are much less efficient in discarding the heat and thus need   much more coolant{{Mdash}}and a commensurately larger reservoir{{Mdash}} to give it time to cool down.

Liquids allow the transfer of more heat from the parts being cooled than air, making liquid cooling suitable for overclocking and high performance computer applications.<ref name="hardwidge">{{cite book|last=Hardwidge|first=Ben|title=Building Extreme PCs: The Complete Guide to Modding and Custom PCs|publisher=O'Reilly Media|isbn=978-0-596-10136-7|pages=66–70|url=https://books.google.com/books?id=ISZnhgYdzIcC&pg=PA72|year=2006}}</ref> Compared to air cooling, liquid cooling is also influenced less by the ambient temperature.<ref>{{cite web|url= http://www.avadirect.com/forum/Blog/11472-Ambient-Temperatures-Effect-on-PC-Cooling/|title= Ambient Temperatures Effect on PC Cooling|author= <!--Staff writer(s); no by-line.-->|date= 17 January 2014|website= Avadirect|access-date= 27 January 2017|archive-url= https://web.archive.org/web/20170202062704/http://www.avadirect.com/forum/Blog/11472-Ambient-Temperatures-Effect-on-PC-Cooling/|archive-date= 2 February 2017|url-status= live}}</ref> Liquid cooling's comparatively low noise level compares favorably to that of air cooling, which can become quite noisy.

Disadvantages of liquid cooling include complexity and the potential for a coolant leak. Leaking water (and any additives in the water) can damage electronic components with which it comes into contact, and the need to test for and repair leaks makes for more complex and less reliable installations.<ref>{{Cite web |title=Look what's inside Linus Torvalds' latest Linux development PC |url=https://www.zdnet.com/article/look-whats-inside-linus-torvalds-latest-linux-development-pc/ |access-date=2024-11-22 |website=ZDNET |language=en}}</ref> (The first major foray into the field of liquid-cooled personal computers for general use, the high-end versions of [[Apple Inc.|Apple]]'s [[Power Mac G5]], was ultimately doomed by a propensity for coolant leaks.<ref name="PowerMac G5 Coolant Leaks/Repairs">{{cite web |url=http://www.xlr8yourmac.com/systems/G5_coolant_leaks.html |title=PowerMac G5 Coolant Leaks/Repairs. |access-date=15 July 2013 |publisher=XLR8yourmac |archive-url=https://web.archive.org/web/20170626164703/http://www.xlr8yourmac.com/systems/G5_coolant_leaks.html |archive-date=26 June 2017 |url-status=live }}</ref>) An air-cooled heatsink is generally much simpler to build, install, and maintain than a water cooling solution,<ref name="murphy">{{cite journal|last=Murphy|first=Dave|title=Maintain Your Water-Cooling Setup|journal=Maximum PC Magazine|date=September 2007|pages=58–60|url=https://books.google.com/books?id=OQIAAAAAMBAJ&pg=PA58}}</ref> although CPU-specific water cooling kits can also be found, which may be just as easy to install as an air cooler. These are not limited to CPUs, and liquid cooling of GPU cards is also possible.<ref>{{cite web|url=http://www.legitreviews.com/nzxt-kraken-g10-gpu-water-cooler-review-on-an-amd-radeon-r9-290x_130344|title=NZXT Kraken G10 GPU Water Cooler Review on an AMD Radeon R9 290X – Legit Reviews|date=10 December 2013|access-date=11 December 2013|archive-url=https://web.archive.org/web/20131213080732/http://www.legitreviews.com/nzxt-kraken-g10-gpu-water-cooler-review-on-an-amd-radeon-r9-290x_130344|archive-date=13 December 2013|url-status=live}}</ref>

While originally limited to [[Mainframe computer|mainframe]] computers, liquid cooling has become a practice largely associated with [[overclocking]] in the form of either manufactured all-in-one (AIO) kits or do-it-yourself setups assembled from individually gathered parts.<ref>{{Cite web |date=2022-05-06 |title=Featured Projects – LiquidHaus |url=https://www.liquidhaus.com/pages/gallery |access-date=2022-05-06 |website= |archive-url=https://web.archive.org/web/20220506071434/https://www.liquidhaus.com/pages/gallery |archive-date=6 May 2022 |url-status=dead}}</ref> The past few years{{when|date=November 2021}} have seen an increase in the popularity of liquid cooling in pre-assembled, moderate to high performance, desktop computers. Sealed ("closed-loop") systems incorporating a small pre-filled radiator, fan, and waterblock simplify the installation and maintenance of water cooling at a slight cost in cooling effectiveness relative to larger and more complex setups. Liquid cooling is typically combined with air cooling, using liquid cooling for the hottest components, such as CPUs or GPUs, while retaining the simpler and cheaper air cooling for less demanding components.

The IBM [[Aquasar]] system uses ''hot water cooling'' to achieve [[Efficient energy use|energy efficiency]], the water being used to heat buildings as well.<ref>{{Cite web|url=http://www.hpcwire.com/hpcwire/2010-07-02/ibm_hot_water-cooled_supercomputer_goes_live_at_eth_zurich.html|archive-url=https://web.archive.org/web/20120813212211/http://www.hpcwire.com/hpcwire/2010-07-02/ibm_hot_water-cooled_supercomputer_goes_live_at_eth_zurich.html|url-status=dead|title=HPC Wire July 2, 2010 |archive-date=13 August 2012}}</ref><ref>{{cite web|url=http://news.cnet.com/8301-11128_3-20004543-54.html|title=IBM liquid-cooled supercomputer heats building|date=10 May 2010|access-date=28 September 2011|archive-url=https://web.archive.org/web/20131101060256/http://news.cnet.com/8301-11128_3-20004543-54.html|archive-date=1 November 2013|url-status=live}}</ref>

Since 2011, the effectiveness of water cooling has prompted a series of all-in-one (AIO) water cooling solutions.<ref>{{cite web|last1=Jeremy|title=Air Cooling Vs Liquid Cooling For Pc What To Choose|url=http://gamesngearselite.com/air-cooling-vs-liquid-cooling/|website=gamesngearselite|access-date=8 February 2017|archive-url=https://web.archive.org/web/20170211091531/http://gamesngearselite.com/air-cooling-vs-liquid-cooling/|archive-date=11 February 2017|url-status=live}}</ref> AIO solutions result in a much simpler to install the unit, and most units have been reviewed positively by review sites.