How-To: Properly Apply Thermal Paste and Install a CPU
Posted 01/26/10 at 10:00:00 AM by Alex Castle
Building a PC is a many-step process, but one in particular stands out as being intimidating to first-timers: properly mounting a CPU and cooler. Why? Because, generally speaking, that one little cpu chip is simultaneously the smallest, most delicate, and most expensive part of your system. Mount the cooler wrong, or improperly apply the thermal paste and you’re looking at (at best) a drop in performance and system crashes, or (at worst) a $200 disaster.
But don’t worry! It’s actually not terribly hard to install a new CPU, as long as you know what you’re doing. And so that you do know what you’re doing, we’ve put together a quick primer on installing a new CPU. If you’re a newbie getting ready to build a new system, or an old pro looking to make sure your technique is the best, read on to find out everything you need to know about properly mounting a CPU.
So what is thermal paste anyway?
Thermal paste is a type of heat transferring agent that serves to fill in the microscopic gaps that naturally occur when two flat metal surfaces—such as your CPU and cooler—are pressed against one another. These air-filled gaps hinder the rate at which the cooler is able to absorb heat from the CPU, and filling them with thermal material greatly increases performance.
There are several different types of thermal material, including ceramic- and metal-based pastes and solid, waxy thermal pads. Some coolers come with pre-applied pads, but most don’t, and we recommend using a paste. Our two favorites are Arctic Silver 5 and Arctic Silver Ceramique.

Step 1: Prep the CPU and cooler
If you’re using a CPU, cooler, or both that’s already seen a tour of duty, then they’re likely to have some gunky thermal paste residue. Don’t be tempted to just reuse this old paste, as it dries out over time, and you won’t get a clean connection between your CPU and cooler.
So the first order of business is to clean off the old thermal material. Here in the lab we use a two-stage cleanser called ArctiClean, although high-percentage rubbing alcohol will do the job just fine. Just apply a drop or two to the old material and let it sit for a minute while the cleaner breaks up the grease in the thermal paste. Then, wipe it clean with a lint-free cloth. A coffee filter makes a terrific, cheap lint-free cloth. Repeat the process until both the CPU and cooler are totally clean, and then move on.

Step 2: Apply the thermal paste
Looking around the internet, you’ll find a lot of different philosophies about how to apply thermal paste. Some people say you should apply it in a dot, some a line, some two lines, some an “X,” and so on. Truth is, all you’re trying to do when applying thermal paste is to get a paper-thin layer of the stuff over as much of your CPU as possible. For that, a dot is pretty much perfect, since a dot will squish into a circle, which will hopefully reach to all 4 edges of the CPU.
Here’s what we recommend:
First, insert the CPU into its socket on your motherboard.
Next, squeeze out a dot of thermal paste directly onto the center of your CPU. Your dot should be about the size of a BB (as in, what BB guns shoot), or a little smaller than a pea. Next, take your cooler and press it straight down onto the CPU so that the thermal paste spreads evenly in all directions. If you feel comfortable doing it, you can use a very very slight rubbing motion as you press down on the cooler to help spread the paste better.

Ideally, you’re now finished. You simply lock your cooler down (using whatever mechanism yours comes with) and then move on. However, if you’re afraid the thermal paste didn’t get spread properly, you can give it a quick look by lifting the cooler back up, twisting slightly to break the vacuum seal that may have formed. If you’ve got too much paste on the CPU, you can wipe up the excess from around the edges, and if you’ve got too little, you can add some more. Of course, if you somehow totally screwed it up, you can always clean everything up and try again.
Note that we don’t recommend doing this more than once—every time you lift up the cooler, you risk adding more air bubbles into the thermal paste, which will lower you coolers efficiency. Don’t let yourself get too worried about that, though—unless you’re doing some real overclocking, it isn’t going to make or break your system.

And that’s about it. Good luck with your build!
WHEN TO RE-APPLY PASTE
Submitted by sdbshb on Sun, 02/14/2010 - 10:47am
I see a couple people have asked how long before re-applying the thermal paste on their CPUs. The Answer is easy... The majority of pastes require an annual reapplication like AS5 and Tuniq... if you really want to know look on their official website. There are few pastes that last longer than that officially... one being arctic cooling's MX2 or MX3 which lasts eight years. Once again I suggest going to the official site of whatever paste you are currently using and check. Again you get what you pay for!
I Just Pea on my Chip..
Submitted by Metalmorphasis on Tue, 02/09/2010 - 10:45pm
Right dead in the center. Works perfect all the time no crap!
If I were a company selling
Submitted by Alperian on Fri, 02/05/2010 - 4:59am
If I were a company selling these 'preparations', I would probably recommend using 25 gallons per virtual core. The whole article above was summed up in the line:
"...agent that serves to fill in the microscopic gaps that naturally occur..."
All this BB sized stuff is inaccurate and excessive. One does not need to be an engineer in thermodynamics, or quote the second law to know that just a thin smear is all that is needed.
Diplomacy is the art of saying 'Nice Doggy' until you can find a rock.
Maybe you should contact the
Submitted by QuakindudeMod on Fri, 02/12/2010 - 3:14pm
Maybe you should contact the guys who make ICD7 and teach them something. Because the way the article you've commented on recommends to do it is correct. It's also the way just about every manufacturer of thermal interface material recommends to apply it. And for a general, all around method of application, you can't go wrong using it.
*****MaximumPC Moderator. Report inappropriate/SPAM comments to
QuakindudeMod at Gmail--dot--com with a link. My personal comments do not necessarily
reflect the opinions of MaxPC or Future US*****
Mask it
Submitted by Audie on Wed, 02/03/2010 - 3:32pm
I'm lazy but tidy. I use masking tape to create a square exposed area on the CPU about 1/8th inch from its edges. I lay a bead of paste on one side of the masked square and use a credit card to spread a think, consistent layer of paste. Remove the masking tape and you are good to go, just like the pre-applied pastes. When I remove a sink, I find the pressure has typicall spread the paste exactly to the edges of the CPU. The scraper tends to accumulate paste and it can be a little wasteful. One of these days I reckon someone will create and market little masks.
Arctic Silver has specific
Submitted by LD on Wed, 02/03/2010 - 3:30pm
Arctic Silver has specific instructions for the Core i7 and i5. You don't use a single dot in the center of the CPU. Instead you use a small line of paste oriented according to the cores.
You mean you dont use 3
Submitted by ironious on Mon, 02/01/2010 - 11:17am
You mean you dont use 3 tubes and spread it all over the heat pipes like inside my laptop?
sounds like somthing apple's
Submitted by schneider1492 on Sat, 02/06/2010 - 7:57pm
sounds like something apple's authorized techs would do. lol
I'd like to ya try the bb /
Submitted by Athlonite on Mon, 02/01/2010 - 3:38am
I'd like to ya try the bb / pea size drop with Shin-Etsu's thermal compound LOL you'd push your CPU throught to the other side of you mobo and on to china befor it spread like that
ASUS M3A32MVP-DELUXE AM2+, AMD Athlon x2 7750BE @ 2700MHz + Tuniq Tower 120
2x Corsair Dominator Twin2x2048C5D-8500 (4x 1GB) DDR2-1066MHz 555-15CL2 2.10v
HIS Radeon HD5770 FAN 1GB DDR5 cclk/850MHz memclk/4800
2x WD2500AAJS Raid0 Boot/
i just used a pea sized
Submitted by nekollx on Mon, 02/01/2010 - 10:09am
i just used a pea sized square then lowered the fan on.
------------------------------
Coming soon to Lulu.com --Tokusatsu Heroes--
Five teenagers, one alien ghost, a robot, and the fate of the world.
TIM Application
Submitted by rludwic on Sun, 01/31/2010 - 9:57am
I'm using a Prolimatech Megahalem and find the 2 line divided by thirds on the CPU works out best for me. I also found that OCZ Freeze works much better than AS5 and my previous favorite Zalmans Super Thermal Grease 1. The OCZ Freeze has my overclocked I7 (4.2GHz) running at idle at 34C and at 100% load in LinX at 76C. Pretty decent temps for an air-cooled 4.2GHz I7 (1366 pin).
when i apply the paste, i
Submitted by pl4t0 on Fri, 01/29/2010 - 7:55pm
when i apply the paste, i always go through a meticulous process of using a credit card to spread it very evenly, just right. I used to use the method displayed in the article, but once I was very careful and cautious about how it was spread, it LITERALLY lowered my CPU temps by about 8-9 degrees.
I was wondering how long
Submitted by Carlidan on Thu, 01/28/2010 - 1:59am
I was wondering how long does thermal paste last before you have to reapply it?
“Animals, whom we have made our slaves, we do not like to consider our equal.”
because it's a grease, if
Submitted by pl4t0 on Fri, 01/29/2010 - 7:57pm
because it's a grease, if I'm not mistaken, I don't think you ever have to reapply it, because it'll never harden or substantially change its state. But there is the definite possibility i'm mistaken, this is just in my own experience.
Cleaning
Submitted by mikebravo on Tue, 01/26/2010 - 7:36pm
Say Yull, why not pop down to the local liquor store and buy Everclear or the equivelent. At 190 proof it will clean most anything, including your stomach lining.
Use Goof-Off to remove old paste. Box cutter blade for install.
Submitted by JohnP on Tue, 01/26/2010 - 4:29pm
The best stuff for removing old paste is Goof-Off, available in Home Depot and probably grocery stores. That is not Goof-off 2 or whatever its called. Follow the cleaning up with isopropyl alcohol.
Artic Silver 5, a highly rated paste, will not work well with a wipe on technique as it is very sticky. The best way is with a sharp metal edge. I use an old box cutter blade that I dulled up some.
That's interesting
Submitted by jongalt26 on Tue, 01/26/2010 - 12:02pm
MPC used to recommend spreading it with a ziplock bag over your finger. This is the first time i think i've seen them use this method. Peronally i don't care for it very much. I also didn't like the ziplock bag method either. Typically i just take a razer blade and spread it evenly with that. It's easy enough.
Im wondering if Gelid or IC Diamond 7 is better, i'll have to look into that.
j
Read my post below on
Submitted by DBsantos77 on Tue, 01/26/2010 - 8:34pm
Read my post below on Gelid compound.
-Santos
I much prefer the ziplock
Submitted by ghen on Tue, 01/26/2010 - 1:46pm
I much prefer the ziplock bag method. This way I can make sure I get a nice even spread before plopping down the heatsink. No second guessing. It takes a while to get perfect, but I'd rather take the time than worry when I push the OC'ing boundries.
Interesting stuff...
Submitted by HeartBurnKid on Tue, 01/26/2010 - 10:32am
I usually use a plastic bag to smear the thermal paste evenly around the CPU. Never tried just letting the weight of the HSF do it for me. Wonder how the techniques compare... this one is definitely less work.
tis all good if your using a
Submitted by Athlonite on Mon, 02/01/2010 - 3:41am
tis all good if your using a fairly runny type of TIM anything thick like the shin-etsu stuff and you need to spread it first
ASUS M3A32MVP-DELUXE AM2+, AMD Athlon x2 7750BE @ 2700MHz + Tuniq Tower 120
2x Corsair Dominator Twin2x2048C5D-8500 (4x 1GB) DDR2-1066MHz 555-15CL2 2.10v
HIS Radeon HD5770 FAN 1GB DDR5 cclk/850MHz memclk/4800
2x WD2500AAJS Raid0 Boot/
Cleaning then DRYING
Submitted by Modred189 on Tue, 01/26/2010 - 10:29am
As another tip, when i clean off my CPU TIM, after using alcohol to get the old TIM off, I use a bottle of compressed air to evaporate any remaining cleaner.
70%+ alcohol
Submitted by johnny3144 on Tue, 01/26/2010 - 2:51pm
high % alcohol evaporate by itself in seconds.
This is great
Submitted by Tophar on Tue, 01/26/2010 - 10:18am
I would really love to see more articles like this targeted at first time computer builders.
i always though their walk
Submitted by nekollx on Tue, 01/26/2010 - 10:29am
i always though their walk thoughts for building their custom pcs covered all the main points. Only this was really missing details..
------------------------------
Coming soon to Lulu.com --Tokusatsu Heroes--
Five teenagers, one alien ghost, a robot, and the fate of the world.
AS5 is good
Submitted by DBsantos77 on Tue, 01/26/2010 - 10:07am
Meh, Arctic Silver 5 is good, but way outdated. I switched to Gelid Extreme Compound, keeps my 3.6 Ghz Phenom @ 17 C on Idle, 35 C 100% load with Prime. Gelid is five degrees lower in both scenarios, respectively. I also did avery sloppy job on spreading it, I'm probably going to follow this tut when I get home and re-apply the compound.
Gelid kicks AS5's ass when cooling, but it's pricey, I paid $18 for my compound from the 'egg.
Also, Gelid's compound doesn't require the "set-in" time that AS5 requires, which is four to five months for the compound to work at peak performance...pretty long time if you ask me. I clean out my machines dust every month, including the CPU heatsink.
-Santos
How cold is the room where the comp is?
Submitted by nsvander on Thu, 03/04/2010 - 12:29am
By my estimates, 17C is around 63*F and 35C is around 94*F, so how cold do you keep the room where your PC is?
wow! now i know what to do
Submitted by OBAMALIAR on Tue, 01/26/2010 - 9:54am
do i apply a dot or an x pattern to my toothbrush? ive been waiting for guidance cause im scared to go it alone
How timly, I JUST not my
Submitted by nekollx on Tue, 01/26/2010 - 9:17am
How timly, I JUST not my new CPU yesterday, and am hoping the new HDDs arrives today for a new build of the family pc.
------------------------------
Coming soon to Lulu.com --Tokusatsu Heroes--
Five teenagers, one alien ghost, a robot, and the fate of the world.
AS5? Really?
Submitted by Spartacus on Tue, 01/26/2010 - 8:26am
Welcome to 2005... What about Tuniq TX-2, 3, and IC Diamond 7? Swapping a cooler's paste from AS5 to TX-2 lowered temps by 4C and from TX-2 to IC Diamond 7 dropped another degree. AS5 was the best. Keyword: was.
Rule of Thumb
Submitted by Lummoxx on Tue, 01/26/2010 - 6:01am
In response to some of the questions, the end goal is to have a thin as possible layer of thermal paste between all contact points of the heat sink and CPU.
From what I understand, the "perfect" heat transfer occurs between the metal to metal contact, and the paste is intended to fill any gaps. For example, a truly perfectly flat heatsink, mated to a truly perfectly flat CPU, would require no thermal paste at all. And by perfectly, I mean exactly that. Since even the cleanest cut by the most modern equipment still looks like a jagged forest under magnification, this is a currently unattainable ideal, and hence, the use of thermal paste.
I remember when lapping the heatsink was often brought up in these conversations, I guess it's fallen out of favor? It was done since even the best heatsinks had visible grooves from the manufacturer. I spent quite a bit of time once giving a heatsink a near mirror contact surface. Not saying it was time well spent, but... :)
Oh god, don't reminde me of
Submitted by Stomy on Tue, 01/26/2010 - 6:15am
Oh god, don't reminde me of lapping, not that it's gone to the way side but most of the "air cooler" click argue the point of it as it can be hard to judge peoples results. I sill recomend it for the water cooling and above (hey if your going to put that much effort into a cooling solution you might as well go all the way. but yeah my friend and I falt myself fo not watching him as he did it, but he laped a hole into his first old P4 prossesor I still regret not taking a picture of it lol.
I have applied my fair share of thermal paste but...
Submitted by Devo85x on Tue, 01/26/2010 - 5:42am
Do you have any tips on removing it? I am upgrading my liquid cooling setup and need a way to get the paste off the cpu so I can change the waterblock, any tips?
Its on step one. High
Submitted by m1k3_flrs on Tue, 01/26/2010 - 9:10am
Its on step one. High percentage alcohol will work on removing the residue of old thermal paste....
Removing thermal paste
Submitted by Yull on Tue, 01/26/2010 - 6:56am
Use isopropyl alcohol!
In most cases - at least here in Europe - rubbing alcohol is made with ethyl alcohol mixed with water or acetone or methyl alcohol, these additives decrease somewhat the capacity of grease removal...
For me...
Submitted by K0BALT on Tue, 01/26/2010 - 6:40am
When I do it............. I wipe off the old paste with a dry, lint-free cloth. Then get another clean cloth and use rubbing alcohol to finish it off. Acetone works well also.
_______________________________________________________________________________
~ i7 920 @ 4.4GHz, (2) GTX295's Quad-SLI, EVGA X58 3X SLI, 6GB DDR3 OCZ Gold ~
I prefer....
Submitted by K0BALT on Tue, 01/26/2010 - 5:26am
... the 'X' pattern of paste on the cpu tends to spread better than the traditional dot, in my experience. I actually just tested both ways last night with my i7 and a waterblock.
Heatpipe coolers should use 2 lines about half the width of the cpu on the base in between the pipes.
_______________________________________________________________________________
~ i7 920 @ 4.4GHz, (2) GTX295's Quad-SLI, EVGA X58 3X SLI, 6GB DDR3 OCZ Gold ~
How long's it last?
Submitted by brotherj on Tue, 01/26/2010 - 4:55am
"Don’t be tempted to just reuse this old paste, as it dries out over time"
If I don't do any upgrades to cooler, cpu, or mobo for a couple years, how long would you recommend I wait before putting on a fresh coat?
unless it says how long a
Submitted by Athlonite on Mon, 02/01/2010 - 3:30am
unless it says how long a life it has on the packaging then every 12~24 months dependent on the quality of the product your using
"i ride sheep"
ASUS M3A32MVP-DELUXE AM2+, AMD Athlon x2 7750BE @ 2700MHz + Tuniq Tower 120
2x Corsair Dominator Twin2x2048C5D-8500 (4x 1GB) DDR2-1066MHz 555-15CL2 2.10v
HIS Radeon HD5770 FAN 1GB DDR5 cclk/850MHz memclk/4800
2x WD2500AAJS Raid0 Boot/
thats a hard question to
Submitted by Stomy on Tue, 01/26/2010 - 5:17am
thats a hard question to answer for a few reasons, some thermal paste clame their product works best after it "cures". Some can degrade over time all though that is very rare. I would recomend running something like Speedfan- www.almico.com/speedfan.php do a through cleaning and record the temps, after a few months do another cleaning and compair. If after a while you notice a increase in temp then hey go ahead and redo your paste and see if that helps.
COOLER MASTER Hyper 212
Submitted by Stomy on Tue, 01/26/2010 - 1:33am
Just a quick question, what about the heatsinks with the exposed heat pipes? I.e. COOLER MASTER Hyper 212 is there any special consideration to be taken with these as there is a chance to have some of the thermal paste being sucked in-between the base and the pipes? It's just something I was considering now that I’m looking at building a new rig and knowing the 212 is your new best of the best in air cooling (even though the website hasn't updated it yet). I personally don't even know if that possible but it seems like it could happen knowing my luck lol.
CM 212+
Submitted by booim on Tue, 01/26/2010 - 6:12am
Yes, I was wondering if I had done it the right way. At full load, using this CM 212+ I only get -15°C differences compare to the stock cooler.
I usally use the
Submitted by cyclo on Tue, 01/26/2010 - 5:49am
I usually use the "bb-gun/rice grain in the middle" approach but for my CM Hyper 212 Plus, I applied a layer of AS5 on both the CPU heat spreader and the 4 exposed copper pipes making sure the layers are thin by scraping off excess paste with a razor blade.
This approach makes sure the paste gets into the exposed copper pipes and not trapped in the area between the pipes.
Seconded.
Submitted by CloudRider on Tue, 01/26/2010 - 4:53am
I was just wondering the same thing.
just what i did.
Submitted by bikerbub on Tue, 01/26/2010 - 5:44am
i did some lines of paste along the grooves of the pipes on the bottom, then some extra on the cpu itself.
Feature
Review
Feature
Feature
Feature






