Does Thermal Compound Matter

[Computer-Ed]

Thermal Compound is the unsung hero of CPU cooling. It is the material that sits between your massive heatsink and CPU, making sure that at all times a good contact has been made. Over the years thermal compounds have been the source of discussion when it comes to how to apply it and which is best.

Currently in the industry the recognized standard of Thermal Compound is Artic Silver. Some have claimed as much as a 5c temperature difference by using the correct compound, are these claims true?

For purposes of these tests we will use three different compounds, Zalman ZM-STG1, Arctic Silver Ceramique and a generic white compound from a local computer store.

For purposes of this test temperatures where not recorded until the system had been running for 3 days to allow the compound to setup. The system used was an E6600 overclocked to 3.2 Ghz with a Thermaltake Big Typhoon VX cooler in an Antec Nine Hundred Case. To ensure the load of the cooling was on the cooler, thus testing it's contact, the fans on the case where set to low. Testing was performed in a room temperature of 30c. All testing was recorded when the processor was under load for at least one hour using Folding@Home dual core client. before applying the compound for each test the CPU and heatsink where cleaned with Arctic Silver Cleaning solutions.

Zalman ZM-STG1 is a bit different from the typical thermal compound. Rather than coming in a tube that your squirt out, this compound is applied with a brush from the jar.

The compound is bit thinner than other compounds tested and so the brush system works really well. Zalman's instructions call for the compound to be spread lightly on the heatsink base and the CPU.

The compound applies cleanly and smooth, making it the easiest of the three tested to install.

Artic Silver Ceramique is considered one of the premier thermal compounds on the market today, it is one of the standards the others are judged by.

The compound comes in tube dispenser as a thick compound. The application directions call for a bead to be applied to our dual core processor, vertically on the processor.

The tube took a bit of effort to force out the compound. The bead method is easy to apply but leaves a bit of guesswork on how thick. You must be careful to not let the compound pool up at the start or end of your bead.

Finally we have our generic compound. This compound claims it is silver based and comes in a small pouch. Unlike the other two it only has enough for a single application and has no way to reseal if you did not use it all anyway. For purposes of application you cut a hole in the pouch and squeeze it out.

With no instructions I decided for testing to use the tried and true method of spreading the compound using a credit card on the CPU. This compound fell between the other two in terms of how thick it was. It was the messiest and slowest to install of all the compounds.

Now that we have our three compounds lets see what each delivered. Temperatures reported are the highest core temp readying using Speedfan.

• Generic Compound: 52c
• Zalman Zalman ZM-STG1: 47c
• Artic Silver Ceramique: 46c

To be honest the results surprised me. I firmly expected that the choice of compound would make only minor differences in the cooling of the CPU. When the test results of the Zalman hit I was really surprised at the level of drop that had taken place.

Now while this does show a nice drop from a generic compound, not the only 1c difference between the Zalman and Artic Silver. I think it is a fair conclusion to draw that at the higher end of the thermal compound market the differences will be less noticeable.

When you realize that even some of the highest end compound sell for around $10 the effects become even more dramatic. I mean for around $10 you can cut around 6C from the temperature of your CPU under load. We spend more than this many times to cut less with a new case fan.

Now in this testing I did use a heatsink cleaning solution, ArtiClean. This cleaner is a two step compound that REALLY works. Step one will eat any thermal paste or compound for lunch and let it easily wipe away. Step two follows this and finishes the cleaning, making the surface as clean as is possible.

Some will claim that the use of alcohol is enough, and it likely is but for my money this is without a doubt the best way to clean a heatsink and CPU of the generic junk thermal pad the stocks heatsinks come with. $10 buys you enough to do a few heatsinks and CPUs, if you are not making a lot of changes to your system go in with some buddies and buy a community cleaner set, it really is worth it.

I would suggest from this test that no heatsink be installed using stock or generic compound material. A little extra time at the beginning of the build will ensure a cooler running PC.

As for which compound I think is best? On that matter I am torn. Ceramique delivered the best numbers and Artic Silver has the best reputation. However the Zalman I really felt was the easiest to apply correctly. In the end I think I would consider this a tie and recommend either product without reservation. If you are going to use a Zalman 9700 cooler for your CPU the good news is this comes free with the cooler.

[stinger608]

Good article Computer-Ed!!!!

[Tyreal]

Great article!

But what do you mean by Zalman was the easiest to apply? I'd say any AS product is the easiest. On an IHS simply slap a small rice sized grain on and you're done.

[Capper]

Ty, have you ever used the Zalman Thermal Compound?

Zalman ZM-STG1 Thermal Grease Review

The stuff is incredibly easy to use, both applying it and removing it....just "paint" it on with the included brush

[One4yu2c]

Originally Posted by Tyreal

I'd say any AS product is the easiest. On an IHS simply slap a small rice sized grain on and you're done.

Or, according to their updated instructions, a thin line down the middle for dual-core processors. Too much or too little though, and it becomes counter-productive.

[Tyreal]

Originally Posted by Capper

Ty, have you ever used the Zalman Thermal Compound?

Zalman ZM-STG1 Thermal Grease Review

The stuff is incredibly easy to use, both applying it and removing it....just "paint" it on with the included brush

I've seen it around and read about it. Personally I find just putting a small dot or a line is much easier than "painting" it on. I'm impressed by it's performance, I remember reading a long discussion about it somewhere.

As for the thin line method, I haven't heard about it until now. Thanks for letting me know, I might try it next time.

[Jokerswild]

Try toothpaste and vegemite they will both work as thermal grease for about a half hour before they go bad and give decent temps.

[Lead Head]

Originally Posted by Jokerswild

Try toothpaste and vegemite they will both work as thermal grease for about a half hour before they go bad and give decent temps.

Another reader of DansData I see

[Computer-Ed]

While the bead seems easier there are issues when doing it. First the compound could be cooler and thus thicker meaning more pressure is needed to get the paste to come out. A glob at the front can block the paste at first. All of these are really minor but they can easily result in way to much paste being applied.

Also the bead or drop does not always detach itself from the tube easily and you can end up dragging it around fairly easily.

Now I am not saying the difference is HUGE, I am saying for the average user wanting to make 100% sure he does it right with no muss that the Zalman is a little easier out of the gate.

[polobunny]

You didn't let the silver compoud cure, though. Silver compounds need curing.
I'm not sure it would change something however, it's still cheap compound.

BTW, instructions for dual core AMD and dual core Intel processors differ on Artic Silver website. Thin line for Intel, small dot for AMD.

Edit: Oh and in my honest opinion, Zalman is the easiest to apply. It's true you can easily botch the application of Artic Silver ceramique (or any thermal compound in a tube for that matters) but it would be really really hard to apply Zalman paint on compound in a wrong way. It doesn't give the "best" performances but it's still more than decent.