Puget Systems print logo
Read this article at https://www.pugetsystems.com/guides/170
Article Thumbnail

Thermal Paste Application Techniques

Written on November 12, 2012 by Matt Bach


No man-made surface is perfectly smooth, and the tiny gaps between a CPU and a heatsink are usually large enough to have a negative impact on cooling. To combat this, thermal paste is used to fill in these air gaps. The thermal paste itself is not as thermally conductive as metal, however, so it is important that not too much is used. If that happens, the thermal paste will behave more like an insulator than a means of improving thermal performance.

Heatsink air gap

The best technique to apply thermal paste is something that is often debated on the internet, so in this article we want to do our own testing to find the best method for applying thermal paste. First we will see how each technique spreads the thermal paste across the CPU, and then we will test each technique in a full computer system to see which has the best thermal performance.

Test Setup

To get a clear view of how the thermal paste spreads for each technique, and to see if the spread results in any air bubbles, we fabricated a 3/8" thick acrylic plate to act as an interim heatsink. This acrylic plate has portions removed to clear the capacitors around the CPU, and the mounting is the exact same size and spacing as the Corsair H60 CPU Cooler. This way, we can ensure that our results match exactly what you would see when using a real heatsink.

Thermal Paste Spreader Top Thermal Paste Spreader Bottom
Top of the acrylic heatsink analog Bottom of the heatsink analog
Thermal Paste Spreader In Place Thermal Paste Spreader Secured

For our thermal testing, we will be using the following components:

Testing Hardware
Motherboard: Asus P8Z77-V Pro
CPU: Intel Core i7 3770K 3.5GHz
CPU Cooler: Gelid Tranquillo Rev2
RAM: 2x Kingston DDR3-1600 4GB
Video Card: Intel HD 4000
Hard Drive: Intel 320 120GB SSD
Chassis: Open Air Test Bench
Thermal Paste: Arctic Cooling MX-2
Thermal Paste Testing Station

CPU temperatures were recorded with a combination of CoreTemp and Speedfan with the temperature reported as the average of the four cores. We let the system idle for at least 45 minutes before recording the idle temperatures, and to put the system under 100% load we ran a combination of both Prime95 and Furmark. Dynamic fan ramping was disabled from the motherboard since we are primarily concerned about the variances in temperature between each application technique and do not want the fan throttling to affect our results.

We are using the built in video controller to help put just a little extra load on the CPU which should accentuate any temperature variances. An open-air test platform was used in place of a chassis since it should allow for more consistent results.

Application Techniques

The techniques we are testing come from the common recommended techniques found online as well as a few we devised ourselves. We made sure to apply the paste evenly, but did not make it 100% perfect. We did this on purpose so that our results would be consistent with what you would see in the real world.

Thermal Paste Rice sized dot Thermal Paste 2x rice sized dot Thermal Paste thin line
Rice sized dot in the middle 2x rice sized dot in the middle Thin line across the middle
Thermal Paste thick line Thermal Paste Three thin lines Thermal Paste spiral pattern
Thick line across the middle Three thin lines Spiral pattern
Thermal Paste rough spread Thermal Paste smooth spread Thermal Paste X shape
Roughly spread across CPU Smoothly spread across CPU X shape
Thermal Paste circle shape Thermal Paste circle shape with dot Thermal Paste happy face
Circle shape Circle with dot in the middle Happy face

Each of these techniques (with the possible exception of the happy face) have some merit to them. The single dot or line should have few air bubbles, but likely will not cover the entire CPU. At the same time, the spiral pattern will likely cover the entire CPU, but may have some air bubbles. To find out, let's take a look at how each technique looked after installing our acrylic heatsink stand-in.

Spread Results

It is almost impossible to see the tiny air bubbles in the images below, so we went ahead and circled them in blue. Larger air bubbles have larger circles, while smaller bubbles have smaller circles. Similarly, any areas where the thermal paste did not cover the CPU are circled in red.

Thermal Paste Spread - Rice sized dot Thermal Paste Spread - 2x Rice sized dot Thermal Paste Spread - Thin line
Rice sized dot in the middle 2x rice sized dot in the middle Thin line across the middle
Thermal Paste Spread - Thick line Thermal Paste Spread - Three thin lines Thermal Paste Spread - Spiral pattern
Thick line across the middle Three thin lines Spiral pattern
Thermal Paste Spread - Rough Spread Thermal Paste Spread - Smooth spread Thermal Paste Spread - X shape
Roughly spread across CPU Smoothly spread across CPU X shape
Thermal Paste Spread - Circle shape Thermal Paste Spread - Circle shape with dot Thermal Paste Spread - Happy face
Circle shape Circle with dot in the middle Happy face

The first thing to point out is that the single dot and line had almost no air bubbles, but they did not spread across the entire CPU. Even doubling the size of the dot still did not cover the entire CPU as the majority of the extra thermal paste simple squirted out the sides. Using three lines instead of one helped with coverage, but resulted in more air bubbles.

Both roughly and smoothly spreading the thermal paste across the CPU had great coverage, but resulted in quite a few small air bubbles. These air bubbles are tiny compared to the circle and spiral shapes and likely to have a minimal effect on performance, but they are definitely present. Spreading the thermal paste perfectly should result in fewer air bubbles, but in our experience it is impossible to get it 100% perfect.

Surprisingly, the X shape resulted in the best overall spread with great coverage and very few air bubbles. This surprised us a bit, but makes perfect sense when you think about it. The X shape allows the paste to spread equally across the CPU, and since the spread is from the inside out, the shape helps prevent air pockets from becoming trapped.

Unfortunately, the happy face did not have great coverage and resulted in a few relatively large air bubbles. But the biggest factor for each technique is how well each actually cools the CPU, so let's take a look at our thermal testing results:

Temperature Results

Thermal Paste Application Technique Thermal Results

Overall, the thermal results are pretty close to what we expected given our spread testing. The X shape, with the best coverage and fewest air bubbles, performed the best at 54.25°C under full load. The smooth spread was close behind and was only .25 °C hotter under full load. Surprisingly, the rice sized dot tied with both the happy face and the circle with dot for third place at 54.75 °C.

Interestingly, the 2x rice sized dot and thick line - both of which had quite a bit of excess thermal paste that got squeezed out from between the CPU and the heatsink - did the worst in the thermal testing. This reinforces the idea that, just like too little thermal paste, too much thermal paste can result in sub-standard performance. 


Thermal Paste ApplicationFor years, we at Puget Systems have used either the rice sized dot or the smooth spread technique in our builds depending on the system requirements. Smoothly spreading the thermal paste takes time and effort to get exact, however, so the fact that our testing shows a simple X shape performing even better is absolutely great news. Not only is it a much simplier application technique, it is also much easier to keep consistent. And for those that are wondering, it works just as well on larger CPUs like the Intel socket 2011 CPUs. The thickness of the line just needs to be very slightly increased, and the X shape should be extended to cover the entire face of the CPU.

Perhaps our most interesting result is that if you are going to use the tried-and-true rice sized dot, you might as well have a bit of fun and draw a little happy face instead. Not only does it cool just as well, but you can rest easy knowing that you have a happy, smiling CPU underneath your heatsink.


Best Performance:
X Shape

Thermal Paste best application technique

Tags: CPU, Cooling, Performance, Advice, Temperature, Thermal Paste

What would be the most optimal amount of paste and spread method for a processor without an integrated heatsink? For instance, a laptop processor with just the die coming into contact with the base of the heatsink?

Posted on 2012-11-13 02:43:56

For something like that, I would use the smooth spread method. Getting perfect coverage on a non-square shaped die is going to be difficult unless you do the spreading yourself. If you are unsure if the coverage is good or not, it's usually a good idea to apply the thermal paste, install the heatsink, then remove the heatsink and see how well it spread. Check that the entire die is covered and that not too much was pressed out the sides. You will want to clean off the die and heatsink and reapply the thermal paste, but at least you will know for sure if you are using the right amount.

Posted on 2012-11-13 08:52:40
Semer Pettersen

Great test.
But how about a test the other way around. Take different heatsinks and test how they fair with the different metods? Some heatsinks that have the copper tubes directly onto the CPU, have gaps bethween the tubes, which metod is right for that

Posted on 2013-04-01 09:25:53

In other words, as long you use the right amount, any of the tecniques are the same realy. So its up to what one the person has more experience and confort to apply.

Posted on 2013-06-11 07:30:43
James Childress

I think the reason your smooth spread has so much air trapped was because it was not smooth. It had a lot of texture to it. I just installed a cpu today using the smooth method and I took the time to smooth it as flat as possible. The result was a CPU that with the stock cooler was easy to OC about 300 mhz above stock (3.8ghz to 4.1 Ghz) speed and still be within safe operating tolerances.

Posted on 2014-03-01 14:43:40

Thank you. Best I see so far.

Posted on 2014-04-09 21:29:10

how to apply the or spread the paste ?? plz elaborate

Posted on 2014-04-30 16:11:04
Steve Bike

Piece of scotch tape over your finger, with the sticky part adhered to your finger tip. Then just smooth it out evenly.

Posted on 2017-05-03 19:41:43

You'd get slightly better line results if applied paste vertically. That's how the die is located under the heatspreader.

Posted on 2014-05-29 11:03:44

But not if you have a water cooling solution

Posted on 2018-04-30 13:20:01

what did you guys use to torque the heat sink dummy down with? or did the screws have shoulders which allowed them to only tighten to a certain clearance? Also it seemed like a lot of the other shapes could have worked better if they were just applied thicker and had more squeeze out.


Posted on 2014-07-22 18:38:53
Facts Appear Directly Below

This is what Cisco recommends for use on Xeon CPUs in some of their blade servers, so it looks like the X shape is well-regarded.

Posted on 2014-08-07 08:55:02

One thing that stands out to me here is - the spread from best to worst is 0.5C at idle and 2C at full load. What that tells me is, the technique you use isn't NEARLY as important as is often thought/claimed!

Posted on 2015-01-06 16:34:45

The other point that was not mentioned was how much paste the different methods uses. Obviously, the rice grain uses the least paste, and the smooth, "X", other methods use much more (expensive) paste. In a price/performance comparison, the rice grain would offer the best protection for your dollar.

Posted on 2015-01-24 14:53:43

do you realy care about 2 cents more in paste when doing this job ?
its often very expencive to be cheap..
just my 2 cents

Posted on 2015-02-17 11:39:59

I don't care about your 2 cents :)

(Sorry, couldn't resist!)

Posted on 2015-04-26 03:52:29

Quite the contrary, the cost impact of a few extra degrees over several years of running a computer is likely a ton more than whatever amount of 6-10$ paste you might use. In fact, the added burden on your CPU from the heat (and even running extra voltage) affects performance down the line, which is why I rarely overclock. The heat also impacts your motherboard, which in turn also impacts your other parts like RAM, and even the extra case heat can impact things like the video card or hard disks.

Of course, what do I know? I just have the same computer I've had for 11 years, and can play games like Skyrim on high settings with just a graphics card upgrade I did about 5 years ago.

Posted on 2015-09-11 13:20:15

If the X is good, would an asterisk (superimpose + and X) be better?

Posted on 2015-01-27 17:58:36
Facts Appear Directly Below

I think not as it would be more likely form voids (bubbles) between the "legs" of the asterisk. Take a look at the pattern recommended by Cisco that I show above. By using separate dots, it seems they are trying to let air be forced out rather than trapped.

Posted on 2015-02-07 21:34:17
Josh Trewhella

why does everyone hate on the smooth spread? seems like it performs well.

Posted on 2015-03-15 00:28:19

It's fine, but it's messy and fiddly. You spend a bit of effort to wipe it down perfectly smoothly, and you wind up with a card with thermal compound on it and a coverage that doesn't perform any better than if you'd just dropped a blob onto the center.

Posted on 2017-04-13 21:31:38
Randy H.

Smooth spread is the best if done properly. How is it done on pre-applied heatsinks? Always smooth spread. Why not an X?

Posted on 2019-06-17 21:19:25

Sure, if a machine is applying it during manufacturing then that is easy - but when it is coming out of a tube as a cylinder of paste, it takes a lot of extra time to try and flatten that out and get it to the right, uniform thickness. A simple X takes only a couple seconds, and in our testing performed exactly the same :)

Posted on 2019-06-17 21:21:41

Great effort! Thank you!

Posted on 2015-05-10 23:29:25
A Bread

This shows really well that less is more! You should put as less as possible on it but still cover the whole surface!
Of course it's hard to know how much is enough to cover the whole surface (exept you use the smooth spread mothode) when you can't see it spreading like in this test, so just make shure you don't use too much like you see with the "Rize dot" and the "2x Rize dot" methode ;)

Posted on 2016-01-02 00:24:01

You still trust those guys coming into the web and teaching people how to apply the paste. They are crook. Most thermal paste can only dissipate about 3 Wm/k while a metal against metal can dissipate much more heat. Alluminum, for example, dissipate 205 Wm/k, copper dissipate 385 Wm/k. Any paste that does not dissipate heat properly can prevent cooling of the CPU and it will burn faster. If you would turn copper into powder and add it to the thermal paste you would be much safer than going with simple thermal paste. That's life. When you look for chip products they take advantage of your money and cause you conditions to burn your CPU. I remember my Siemens computer that after a couple of year of use lost its graphic card. What did they apply over the graphic card's CPU? The stupid paste right from the factory.

Posted on 2016-02-26 08:23:15
Jan Magne Skaue

No current human tech can manufacture perfectly flat surfaces, and here we're talking mass produced consumer products. Just putting the cooler/block onto the heatspread (direct metal-metal contact) leaves immense amounts of gaps due to surface imperfections. Even if might not be visible to the naked eye, it is most definitely there. Liquid thermal compounds only serve an (extremely) positive function in terms of filling those gaps. Any excess compound beyond that has an insulating effect, so less is clearly more. Its not ideal, but it sums up to a vastly more effective thermal conduction path, than just clamping metal to metal without anytihng to fill those gaps.

Metals (here) are solids. We can grind up those particles pretty small, but they still need to be suspended in something fluid, that /will/ be less thermal conductive. As tiny as possible particles and a perfectly even blend distribution is critical - and us mere mortals don't have access to such equipment. Its simply cheaper to buy a finished product. But there are metal thermal compounds available. They are quite a hassle to deal with, electrically conductive and there is always the chance of galvanic corrosion, depending on heatspread, thermal compound and cooler material. Gains are decent, no miracle - but the product IS available.

Posted on 2016-03-01 17:39:00

Actually there is at least one valid purpose for the liquid metal paste, for Ivy Bridge/Haswell CPU's that will certainly not last 10 years, unless carefully delidded, then cleaned well of the cheap TIM solution (low cost thermal paste) that enthusiasts wouldn't touch with a 10 feet pole. Afterwards, only a tiny amount of the 'liquid metal' should be installed & properly spread, then not only will there be drops in temps, also the CPU will last much longer.

Intel took the cheap way out on these $300+ CPU's & didn't use fluxless solder, as with previous-gen CPU's, from the Sandy Bridge on down, and that's another reason why if one has a powerful Sandy Bridge CPU (2nd gen 'i' series), not to bother with upgrading platforms. Unless the person wants to run the latest features such as SATA Express or PCIe oe M.2 (10Gb/sec) drives. Which will be my next build with the i7-4790K recently purchased, yet want to address the delidding issue first.

Just wanted to let folks know, there is a valid use for metal pastes. Though one must be extremely careful, otherwise will have a $300+ paperweight in a split second.

Will likely have to experiment this first on an 3rd/4th gen dual core Pentium CPU, these are plentiful, cheap (maybe with luck get one on eBay for $40) & can afford to lose one in learning, It's not something that a first timer like myself should do on a $350 CPU. The 3 year warranty is down the drain. What I'm unsure of, what happens should the thermal paste in the CPU does dry out? I'd presume a dead CPU, yet these aren't quite old enough to know, other than Ivy Bridge owners, or which I have one, a Samsung notebook (they no longer manufacture Windows computers), with a i7-3630QM, a true quad core notebook with a 1GB GDDR5 nVidia 640M, it's a hot runner also. Being that it's soldered in, probably little to now way I can delid it to see if that alone would being down temps (in the cores).

Thanks for bringing this up, knew that I wasn't the only one who had heard or metal paste, which in contrast to what some may think, will remain liquid & be a very slick surface in there. Not something to consider using as thermal paste, just a drop on the MB may fry it, by shorting it is some manner, beyond repair.


Posted on 2016-05-25 00:18:17

The paste doesn't dissipate heat, it transfers heat

Posted on 2016-03-15 05:19:21
Jan Magne Skaue

To be fair, this might be a wording/terminology thing. Looking at the formulation of his/her post - probably not native a native English speaking person. There is a slight point to this, but the theoretical advantages to a "metal filler", doesn't translate proportionally to practical results. There are too many other elements involved and other "weak" links in the thermal conduction path from heat source to open air, so as to allow is to work that efficiently.

Posted on 2016-03-16 11:25:37

Yes but if he is not a native speaker, why wouldn't he consult with someone before posting a technical article to the whole world?

Posted on 2017-02-22 04:24:43

The part of the equation your forgetting is the thickness W/mk is watts over a meter(cubic) kelvin(difference in temps). if you shorten the distance in the equation, you greatly increase the watts transferred. When you put a heatsink on a cpu die, you have a thin layer of air in-between the metals, the purpose of paste is not to increase the distance of the metals, but to replace the air which has a 0.02 w/mk. bad thermal past has 100x that thermal conductivity, while good thermal paste has 450x+ that thermal conductivity.

Now if you want some math, lets assume 7w/mk(good paste) lets convert this to 1 milimeter(really overdoing the paste here) on a die that is 40mmx40mm big(LGA 1150 and 1151 size) you then get 16 cubic centimeters, which is 62.5x smaller then a cubic meter. This in the end means our 1mm(really thick for paste) layer is capable of moving 437watts of heat across it and to the metal assuming no interfering factors.

But hey, if you don't trust me then find for yourself. Attach a heat-sink with now paste and see how long it lasts before it blue-screens due to temps, and then test it with paste and see how much nicer it is.

Posted on 2016-04-24 08:54:36

Thanks for the explanation. I believe you. I was tempted to produce some powder from a piece of copper and then mix it with an heat-sink paste. Did you ever try it?

Posted on 2016-09-18 20:59:17

I haven't tried it, i suppose if you ground it finely enough that it wouldn't be a problem, but i think the copper being solid would be a big problem as the little grains of it would cause a bit of a gap.

If you want to experiment with a similar idea, diamonds have 2000w/mk and their a company that mixes diamond powder in their paste:

Here you can find 2 well-done reviews of it and other pastes :
Some of the pastes with higher w/mk perform worse than a paste with less or just not as well as expected because the paste's viscosity(how thin or thick it is) makes a bigger gap with more bubbles between the heat-sink and the heat-spreader.Thisis also why when applying paste its possible to apply too much.

Some of the best performing TIM(thermal interface material) is liquid metal alloys, stuff that melts at near a processors TCase(temperature that it throttles itself to not go over); However be very careful with those since they like to react with aluminium and make it crumbly. Liquid metal Tim's have to be be used with heatsinks with copper or nickle platted copper where the TIM makes contact with the heatsink. Intel uses a nickle plated copper heat spreader as the metal part of their processors, and almost all high end heatsinks are nickle plated copper where they make contact.
Please also note the liquid metal stuff is conductive, so if you get it anywhere but on the heatspreader its typically bad news, and for the most part doesnt like to come off.

Personally I recommend Noctua's paste, it's the easiest to apply and is a top performer as you see on the chart and sells $9(ish) a tube.

Posted on 2016-09-18 23:10:14

Well! If it is so complex to make it work than why they don't sell the CPU already melted with an alluminum cooling grid?

Posted on 2016-09-19 12:04:59

A lot of systems do, mostly in systems that arnt meant to be modified. some laptops, aio desktops, and some servers from intel do involve alot of soldering of the parts together. Part of the reason they don't with parts you assemble yourself is they are catering to people who want to customize what they have.

another reason is that they like modulare componants, so if something breaks it can easily be replaced. Also if things are not soldered, it is easier to upgrade them or transfer them to a new system.

That said intel(if not all tech companies) are known for doing stuff sub optimally, and if you read about overclocking you will see many things people do to "fix" that. For the average user what Intel does it more then fine, and with any decent aftermarket controller and a bit of dust management they will encounter no significant problems with heat.

For the record though, intel has listened to what people asked for and twisted it in a way that betters their proffit margins. The intel default CPU cooler is known to be bad, and the paste is known to be bad. So with skylake and onward, they no longer ship a cooler along with cpu's, leaving the user the task to buy one from a 3rd party. Intel saves money, most people do what they were gonna do anyway.

Posted on 2016-09-20 02:05:54

Here is a example of a a server motherboard where the CPU,heatsink,and motherboard come more or less permently attached to each other.

here is a example of a NUC motherboard, which in short is a laptop motherboard and componants being used as a very energy efficent desktop

Posted on 2016-09-20 02:08:58
Jan Magne Skaue

Tip: smear surface lightly and very sparingly. Mate heatsink to CPU (just press, possibly lock in place. Don't boot system). Separate. Run flat, unused razorblade, sharp edge "trailing" at an angle, across both surfaces (smeared spot on heatsink/cooler, and CPU heatspreader). clean up excess compound. NOW, apply X-formation, /very/ lightly. Remount, you're good to go.

Posted on 2016-03-01 18:24:00

Great idea you've shared, will try this on my next CPU install or repaste job.

Since the computer won't have been booted by your instruction, I don't see anything wrong with this method. May also show if one is applying not enough paste, or didn't lower the heatsink level & the paste went to one side. Which is common with those in a hurry, or maybe a first time job & doesn't realize the importance of taking it easy & keeping the heatsink as level as possible during re-assembly.

Your way is a great one to check & see, after boot, it's too late. No matter how 'soft' the paste may still be, then there for sure will be air pockets if booted then excess is removed & reinstalled. Other than any obviously outside of the CPU after boot, which should be able to be safely removed, yet also a sign that too much was installed, it's best to start over & do your way,


Posted on 2016-05-24 23:31:34

i'd like to reapply thermal paste for my laptop cpu and gpu. so does the cross method the most suitable? between rice dot and smooth spread which one is better?

Posted on 2016-05-06 09:37:56

For laptops, most of the time the die (where you are applying the paste) is not actually square but is rectangular. Personally, I tend to do just a thin line in that case. The spread is pretty good for a rectangular surface and you shouldn't have any air bubbles. A smooth spread should work fine too, but I wouldn't do just a rice dot (since it likely won't spread across the whole rectangle unless you put way too much on)

Posted on 2016-05-06 17:46:00

thanks, i will try it when all of my laptop-dependent work finished first

Posted on 2016-05-07 08:29:29

Maybe I need to redo my notebook that I just installed (upgraded to) a i7-620M, based on this, though mine was square. As always, used the 'rice' size on notebook & pea or oat sized on PC CPU's, and wiggled the heatsink a bit before placing in the screws & tightening, with about 5-6 rounds in a criss-cross pattern. Plus there was the discrete nVidia 425M GPU, often there will be a thermal pad on these, on this model, was pasted. Seems that a GPU, being more fragile, the pad would had been a better idea, as I've had others with these & reused successfully.

Maybe for that purpose, I need to get some of the thermal pad material, however it's distributed, can be cut to size. One thing for sure, one cannot over-tighten the GPU area, otherwise the discrete GPU will crack & will only have the Intel (or AMD) graphics inbuilt into the CPU (or APU). Or a notebook that'll BSOD with every boot.

However so far, the i7-620M has ran at lower temps than the previous i5-480M using MX-4 thermal paste (my favorite) & grab a 4g tube at Newegg when on promo every now & then, doesn't have an 8 year warranty for nothing. Both CPU's runs at 35W and GHz levels are also close to the same, yet the i7-620M doesn't freeze at with a lot running at boot & then opening a browser, unlike the i5. Unfortunately, there were no quad core model for the socket (that I was aware of in the Arrandale M CPU's), and even if it were, more power would be needed, as well as a better heatsink assembly, which also limits notebook CPU upgrades.

Sometimes there's also more than one right answer, as long as the end result is not too much paste, few as possible air pockets, and the CPU is running cooler, that's a sign of success.

However there was one component that temps didn't drop nor raise on, and that was the MB temp itself. Because after 30 minutes of use, Speccy as well as CUPID's H/W Monitor, reports temps between 60 & into the lower mid 70C range. Which for a MB, I feel is kind of high, the notebook was tore down enough to get a good blowing out, and there wasn't much dust at all for a 2011 MSI FX603 purchased new by me early that year. In fact, the initial CPU was released the same quarter I purchased it, so was fresh from the assembly line :-)

Being that the MB has always ran at these temps, I keep it on a cooler in a certain position to blow cooler air through the single intake vent. Maybe I should, being it's long out of warranty, consider a bottom case mod for more air intake? I'm sure there are small round filtered intakes, like those on the side of AMD PC's that has a plastic duct going downwards towards the CPU, that can be used in the part of the case that opens (the access lid), w/out the duct of course. Since there's only one small intake & that's very close to the exhaust, maybe one towards the center (where the GPU is) or opposite side will provide more fresh air to cool the MB?

I'm afraId that no matter how much I can lower CPU temps with the best paste & application method, all will be for nil if the MB is running hot. Maybe it's the discrete GPU causing the MB to run hot, and a vent should be created as close as possible to it. My Toshiba of the same CPU family running an upgraded i5-560M (from i3-370M) doesn't have this issue under normal use, since it runs only Intel HD graphics. Though if I'm running an extended Malware scan both the CPU & MB will heat some, which is normal with notebooks, then cool back down, even w/out a cooling pad. The MSI MB reaches 60C with just casual browsing after 20 minutes & 65-70C when Windows Updates are installing. Speaking of which, the GPU also runs warmer than what I feel to be normal (upper 40's to 55-60C), and the repasting showed no positive (or negative) effect. Makes me wonder if the thermal pad would had been a better choice, if one were on hand?

What do you all think of the ventilation idea? Nothing to lose, other than a bit of time & at most, $10 for a small round filtrated vent w/screws, maybe the size of a 12 ounce soda can end? While I believe MSI has good builds, for what was at the time, an 'upper-mid' gaming notebook at $750, maybe they didn't think much about air intake? BTW, the Toshiba has extra intakes, with grooves in a couple of extra places, on the opposite end of the notebook, under the HDD that now houses an SSD, under the access lid to the RAM & a huge row in the center. No wonder the MB runs 20-25C cooler under normal conditions.

I need to do something, even if it's experimental, the pasting won't cool the MB, which will lead to the demise of an otherwise nice notebook. Had I thought it to be no good, wouldn't had spent $40 for the CPU upgrade.


Posted on 2016-05-24 23:12:08
Kelvin de Leon

^_^ my method :D. by the way nice guide for the new rig builder (Y)

Posted on 2016-06-03 04:18:07
Stephen Mitchell

Did you perform these tests on different thermal compounds, and if so did the results corroborate the results using the MX-2 compound?

Posted on 2016-06-08 10:47:50
Sean Hudson

Last time I built a pc I remember reading somewhere to apply a small dot of paste and spread it out with the hard edge of a credit card, pressing it into the surface of the CPU as much as possible, before scraping off all excess. Then you apply another small dot and attach your cooler. I can't find where I read this nor can I find any reference to this process. I think it had something to do with getting around a so-called "break-in period" of the paste and was supposed to give you peak performance from the get-go. Has anyone else ever heard of this?

Posted on 2016-07-24 01:12:18

I feel like you should have just done individual core temperatures not average

Posted on 2016-08-05 03:05:38

I use a fingertip and dab a thin coat onto the CPU. Then I press the cooler onto it and twist it a little, then carefully pull it off. If there's any bare spots on the cooler I dab some onto them and install the cooler.

That uses the absolute minimum amount while having full contact of the paste on both surfaces.

The bare die CPUs were much easier. Poke a fingertip into the film canister of thermal paste, dab onto the CPU and done.

Posted on 2017-01-30 10:01:26

Bad idea as a finger contains dust and a lot of oils that contaminate the paste.

Posted on 2017-11-12 00:26:05

The quality of the heat sink matters quite a bit. Right now I'm running a FX 6100 CPU with a big hunk of Cooler Master aluminum on it. When I did my usual application of thermal paste I was surprised to find very little transfer to the cooler.

So I cleaned it off, took the fan off then put the heat sink in my bench vise. Then I went at it with a metal file until it was actually flat. Do note that filing a metal surface flat takes practice to learn. I've filed *a lot* of crappy heatsinks flat, going back to when PC CPUs first got hot enough to need them.

So once I got it flat, I pushed it onto the CPU, wiggled it a bit then removed it. Full goopy contact.

Posted on 2017-01-30 10:09:28

when applying methods like the line does it need to be perfectly straight

Posted on 2017-03-03 20:35:05
Jean-Simon Lauzon

Im sad you didnt do the 5 dots techniques (like a Dice). Its what ive used to do since forever, i cant pretend its best but it always made a logical sens to me. Its the closest to X shape and its even less effort to do.

Posted on 2017-03-18 05:15:26
Jose Ramón

Same to me

Posted on 2017-10-17 22:58:23

Air bubbles can be an issue doing that

Posted on 2017-11-12 00:27:15

I'd be interested to see if something like: 4 dots by each corner, with 5 tiny dots forming a plus in the middle, or maybe just one larger dot in place of the additional 5, would hold up. I imagine each of the four outer dots would disperse things fairly evenly, only leaving a few small areas that would need to be taken care of. The biggest I would imagine would be close to the middle, hence the tiny plus.

Overall, I feel like the application of thermal paste is a bit archaic. Surely there should be some kind of solution to replace this. I understand why it's necessary, but it seems weird that a better solution hasn't been thought of yet, since experiments like this one show just how much improper application can affect performance.

Posted on 2017-03-23 17:11:37
Jose Ramón

I would like to see that 5 dots method too

Posted on 2017-10-17 22:58:02
Jesse Levesque

Great coverage from the X Shape? The results look like a perfectly sized thermal pad! That's bullsh-t, where my boots?

Posted on 2017-07-18 19:05:52

Nice comparison but some thermal paste are very thick and it is impossible to spread it out. So, for them which method do you suggest?

Posted on 2017-11-16 16:42:01
Ferran Villalba

Thermal paste recommended for Intel Xeon CPU? The MX-4? The Artic Silver 5? Or another? The MX-4 is the most optimal? Can you endure a year without changing it?


Posted on 2018-02-28 15:50:02

We offer Arctic Cooling MX-2 as our premium thermal compound option here at Puget, and normally only change it if the CPU cooler is removed (at which point we clean it off and reapply). Here is Matt's article on this subject: https://www.pugetsystems.co...

Posted on 2018-02-28 16:36:37
Mait Oliver Hellat

X method is way hot here, getting much better results with rice sized dot atleast on 6700k

Posted on 2018-06-04 12:48:03
Dr. Manos PhD

X shape is the smartest and better way to do it. If done right, there will not be any air bubbles at all.
In your case, there are 4 air bubbles just because you applied the X shape not perfectly. It has to be a perfect X, with straight lines and exactly the same amount across each line of the X. In that way, all trapped air moves out while it's being spread by pressure, through the gaps of the X shape.

Posted on 2018-09-25 12:58:24
Tim Daviess

My AIO came with paste pre applied. Should I clean it off and use something better? I didn’t apply any extra when Installed the cooler.

Posted on 2018-12-09 23:53:14

If it is a decent brand of AIO, and you aren't trying to push for a maximum overclock or something, then it is probably fine. A lot of heatsinks also come with pre-applied paste, as it makes the first installation simpler. However, if you need to swap the CPU or remount the cooler at some point you will want to make sure to have thermal paste on hand, since you can't (or at least shouldn't) re-use paste - it should be cleaned off each time the cooler is removed, and then reapplied.

Posted on 2018-12-10 17:00:32

So far I've always smooth spread the paste and it worked well. I never thought that the 1st or 2nd application techniques are good and I'm surprised how the X shape technique performed well. So I think the Cisco recommendation is also can be a satisfying solution.

Posted on 2019-02-17 06:34:55

Buying a real syringe would also improve results. Smearing is essentially impossible to do correctly. If the diameter of the injector hole was correct, smearing would be unnecessary.

Posted on 2019-03-04 05:22:51
Leonard Ratliff

I realize this is an old article, but you can smile knowing you've gotten plenty of miles out of it and that there are plenty of people still referencing it to this day. I see a few references to it over at TH at least every couple of months.

Enough so that I wanted to also add, although I'd be surprised if the authors are still around responding to replies, that in addition to some of the comments that were made here this test seems lacking in a very fundamental way. That way being the fact that your piece of acrylic is completely flat, while most, maybe all heatsinks are either to some degree convex or concave. That would greatly alter the results because as we know from many lapping experiments there are very few CPU heat spreaders that are totally flat and the same goes for the contact bases on heatsinks. A very, VERY small amount of convexity or concavity will completely skew all these results from a flat analog.

Posted on 2020-02-25 06:03:34

Old is Gold :)

Posted on 2020-04-16 23:15:33

Good grief this is thorough and incredibly helpful. Thank you for taking the time for doing something so detailed and thorough. This answers my question quantitatively.

Posted on 2020-04-27 23:57:49

Strange results. I've always used a single dab about the size of a BB from a BB gun and i always get full coverage on the IHS.

Posted on 2020-07-11 11:38:27
Connor de Wit

What gen I7 is it?

Posted on 2021-01-23 21:18:31
Diskoon Tha

i'd like to reapply thermal paste for my laptop CPU and GPU. so does the cross method the most suitable? between rice dot and smooth spread which one is better?
P.S I have found this site which talks about CPU overheating and solutions. Does this site sound legit to you.

Posted on 2021-05-05 16:33:42
zen strata

The Smiley Face method has merit! It makes you feel happy when you put it on! ;)

Posted on 2021-08-03 00:02:31