I decided to start this faq because of constant questions by new people asking about the best heatsinks and on the suggestion of Nanometer that there should be a sticky on the topic.
There are several factors you should think about when deciding to buy a cpu cooler aside from just pure performance. If you are putting together a system for LAN parties, than you might not want the heaviest tower style coolers. Also pay attention to the mounting style of the cooler. For example, coolers that bolt through the motherboard with a mounting plate on the backside will be more secure than a cooler that just clips on. Certain heatsinks perform better with slower moving fans and others require faster moving fans for best performance, so if noise is an issue pay attention to fan requirements. You could use a fan controller to deal with this issue also. Some cases have a cpu air duct, coolers with horizontal fans would probably be preffered for this type of case. Also pay attention to the space on your motherboard immediatly adjascent to the cpu socket for anything that might obstruct the mounting of whatever cooler you would like to use, although this is not usually an issue.
Now for the most asked question; "What is the best cpu cooler?" Well because of different case designs, different thermal cpu output and other factors it's difficult to say such and such is the best. Right now the most popular consensus is that the that the Tuniq Tower 120 is probably the best by a very small margin, depending on configuration; "coolaler" who has many overclocking posts on this board and holds some overclocking world records uses this cooler. Also when reading reviews you may notice that reviewers don't always use the same types of fans, use different cases, motherboards, cpu's etc.
Thermal paste is very important too here is a guide to proper application of thermal paste. Arctic Silver 5 is one of the most popular and effective thermal pastes. Shinetsu thermal pads are very good if you don't want to use thermal paste. Coollaboratory liquid metal may be slightly more effective than Arctic Silver 5 but is not recommended for begginers as it is more difficult to apply properly and is very corrosive to Aluminum, also it will likely cause a short if you get any on your motherboard.
Almost any heatsink can be improved by lapping the base to improve contact and heat transfer, here is an example of a heatsink lapping kit someone pointed me to.
Recommended air coolers
Thermalright IFX-14 (Initial tests show it to be very good but may not beat out the Ultra Extreme, awaiting more reviews...)
Thermalright Ultra-120 Extreme (New 6 heatpipe version of the Ultra-120, the best cooler currently available!)
Thermalright Ultima-90 (Already tested at several degrees better than the Tuniq Tower-120!)
3RSystem IceAge 120 NEW! (Very few reviews but so far appears to be slightly superior to the Tuniq Tower 120 in some circumstances with the fan on high, comes with a fan cantroller but does not seem to be widely available at this time)
Enzotech Ultra-X (So far superior to the Scythe Infinity by a degree or two and about equivilant to a Thermalright Ultra-120 due to the larger diameter heatpipes used on the Enzotech which is also the advantage the newest Thermalrights have)
Thermaltake V1 (Some tests are showing this to be a little better than the Scythe Infinity and almost on par with the Thermalright Ultra-120 Extreme!)
Tuniq Tower 120 (The reigning champion, [Not anymore!] back in stock)
Thermalright Ultra-120 (One of the best cpu coolers only a hair behind the Tuniq)
Scythe Andy Samurai Master (Very good performance for it's size/weight, close to the Infinity, but a few degrees behind the Enzotech and falls behind the Ninja, particularly at very low fan speeds. One of the better coolers listed here for LAN parties and such due to it's lower profile and lighter weight.)
Cooler Master GeminII (Looks to be a very good cooler so far but not as good as the new Thermalright's and maybe Enzotech. However the Cooler Master is so massive it cools the cpu very well without fans in a case with decent cooling. With 2x 120mm fans it cools the motherboard extremely well because of it's size. NOT recommended for LAN parties due to the massive size and weight. Looks to be a rough equivilant to a Scythe Infinity.)
Scythe Infinity (One of the best and most massive sized coolers around. Ive heard it can be run passive in a well cooled case)
Scythe Ninja (Very excellent all-around cooler for quiet fans.)
Zalman CNPS 9700 LED (Larger version of the popular 9500, comes with 110mm fan)
Thermalright SI-128 (About equal or better than the Ninja in all respects, very good with low speed, quiet fans. World class with medium-high speed fans.)
Thermaltake Big Typhoon/VX (Very excellent all around cooler, new "VX" version has more powerfull adjustable fan. Can be modded by adding BGA memory ramsinks to the base for improved performance)
Noctua NH-U12 (Another very excellent tower sized cooler)
Silverstone Nitrogon NT06 Lite (Inferior cooling to most of the coolers listed here but still very good, perfect fit for small form factor computers and cases with very little space. Comes fanless since it was designed to fit right underneath the PSU in a Silverstone SG01 case, you will need a fan for other cases. Lightweight and low-profile make this a good choice for LAN parties as well.)
Review Links:
Heatsink roundups:
Hexus 2007 NEW!
Madshrimps S775 June 2006
Madshrimps February 2006
Madshrimps A64 2Q 2005
Overclockers
Neoseeker May 2006
Tomshardware June 2005
Silentpcreview
BeHardware May 2005
Xbitlabs October 2005
Chilehardware May 2006
people.overclockers.ru
Bleedinedge
Thermalright IFX-14:
[H]ardOCP NEW!
Thermalright Ultra 120 Extreme:
Mini Review :Thermalright Ultra 120 Extreme
Thermalright Ultra-120 eXtreme Review (Navig)
AnandTech
Thermalright Ultima 90:
xtremesystems
3RSystems IceAge 120:
TechPowerup NEW!
Xtremesystems - (hixie) - 3R System Iceage 120 Heatsink Review NEW!
Enzotech Ultra-X:
X-bit Labs
Virtual-Hideout
Frostytech
PC Perspective
BCHardware
Pro-Clockers
OCIA
Thermaltake V1:
Hartware
Legion Hardware NEW!
BigBruin NEW!
HardwareLogic NEW!
Tuniq Tower 120:
Xbitlabs
Bjorn3d
Virtual-Hideout
OCIA
AMDboard
Bigbruin
XtremeComputing
PCmoddingmy
Velocityreviews
ThinkComputers
Thermalright Ultra-120:
Overclockersonline
Overclockers
Hartware
Frostytech
Neoseeker
SPCR
HardwareLogic
Pro-clockers (Compared to Scythe Infinity)
Madshrimps
Scythe Andy Samurai Master:
X-bit Labs
Silentpcreview
Cooler Master GeminII
Xtremesystems-forum (PCcI2iminal - "Coolermaster Geminii vs Scythe Infinity vs Zalman 9700 vs Noctua NH-U12F")
Hexus (first look, not a review, lots of pics)
Thermalright SI-128
Overclockers
DriverHeaven
Bjorn3D
Thinkcomputers
Hartware
Scythe Infinity:
Hartware
Technic3D
SPCR
Pro-clockers
Bigbruin (Compared to Thermalright Ultra 120)
Overclock3D
vr-zone
Techpowerup
PCPerspective
Scythe Ninja:
Silentpcreview
Overclockers
HardwareHell
Viperlair
VR-Zone
Pro-Clockers
Guru3d
ThinkComputers
Hi-TechReviews
Rojakpot
Overclockzone
Hartware
Zalman CNPS 9700
Computerbase
Obengware
Hardwaresecrets
TomsHardware
Tweaknews
Thermaltake Big Typhoon VX
Hi-Techreviews
Thinkcomputers
Virtual-Hideout
Legitreviews
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