Thermal Paste: Got Any Tips?

[TheFourthHorse]

Well, I’ve been suffering from some overheating problems due to dust build up. I opened up my PC for the second time only to discover (to my horror) that the heatsink and fan are actually one and the same and the dust build between them is incredibly bad. I couldn't clean them as they were so I chose to take the dive and remove them, thus separating the bond of cpu, heatsink, and the dreaded THERMAL PASTE…

 

So anyway, tomorrow I’ll be picking up some stuff to clean and reapply the stuff. I’ve read up on it a number of times before, when considering doing the same for my gpu, but now it’s actually game time and I’m looking for some pointers. So if anyone here has had any experience with this nasty goop, I would gratefuly welcome a few pointers or warnings.

 

 

Here’s the game plan so far:

 

 

- Remove old thermal paste with 99% rubbing alcohol and coffee filters. Make sure surface is totally free of any fibers, hairs, or old paste.

 

- Apply a very small dab of paste to cpu plate and tint the surface into a very five film with an old credit card. Wipe any excess paste from the sides. Do the same with heat sink contact.*

 

- Once surface is tinted, apply a dab of thermal paste to the cpu plate approximitly between the size of a BB and a frozen pea.

 

- Gently place freaking heatsink/fan abomination evenly atop cpu, thus spreading the thermal paste.

 

- Firmly but gently screw heatsink back into place.

 

 

*Arctic Silver recommeneds this “tinting” process to assure the bond but no videos I’ve seen have done this. Bearing in mind that all said videos got shockingly lousy feedback, I’m unsure. What do you think?

[samadchaz]

- Apply a very small dab of paste to cpu plate and tint the surface into a very five film with an old credit card. Wipe any excess paste from the sides. Do the same with heat sink contact.*

 

Wrong!

just apply in the middle of cpu AND put the cleaned heat sink on it, no need to apply on heatsink contact and no need of credit cards

[TheFourthHorse]

- Apply a very small dab of paste to cpu plate and tint the surface into a very five film with an old credit card. Wipe any excess paste from the sides. Do the same with heat sink contact.*

 

Wrong!

just apply in the middle of cpu AND put the cleaned heat sink on it, no need to apply on heatsink contact and no need of credit cards

 

Yea, figured it was Arctic Silver over doing it a little. Thanks for the feedback! Kudos given.

 

Would you say the dose is about right besides that?

Edited May 4, 2012 by TheFourthHorse

[blove]

If either surface were not reasonably smooth I would say "tinting" it would be a good idea, lapping both would be best, but otherwise it is not worth the hassle. Depends on the contact area as to how much to use. With a high pressure mount you will know if you have too much.

[FMod]

1. If you haven't bought it yet, use either Arctic Silver MX-4 or Zalman STG-1. For a newbie the latter is better, much easier to apply.

 

2. DO spread it around until it's a thin layer. But not too thin, it should be see-through, but only just. You should test it: put the CPU down on a flat surface, then press the heatsink over it. There should be almost no spots where no traces of paste were left on the heatsink. Spread grease that got left on the heatsink over these spots. You may need to add some.

 

Coating process should be part of the initial process of spreading the grease. "Tint then put a drop" is an acceptable way if you're lazy, it delivers poor but consistent results.

Generally you should use between 0.1 cc and 0.4 cc (including waste) of thermal grease per CPU-heatsink combo, depending on surface quality and your skill. Aim towards the lower figure. 0.5 cc or more is definitely wrong.

 

3. Test it by running Prime95 or LinX and monitoring the temperature. If it's too high (over 80 C for your CPU non-overclocked in a 20 C room), or higher than it was before, you need to redo it.

[bben46]

Before applying the compound be sure to thoroughly clean both surfaces. If you can, use technical grade alcohol as it has no denaturing agents that can leave a film - drug store alcohol is all denatured to keep fools from drinking it and has an oil that makes it denatured. When the alcohol evaporated it leaves a film of that oil behind. That film will contaminate the compound and cause a slight loss of heat transfer properties.

 

Some premade computers (Dell etc) use a heat sink pad instead of compound. That pad will likely break up on removal and should not be reused. Be sure to clean all of the residue from the pad before applying compound.

 

The biggest mistake I see is using too much compound. A thin layer is all that is needed. More is not better and can actually lead to overheating.

 

Otherwise - what Fmod said will work fine.

[TheFourthHorse]

@bben46

 

I’ll certainly keep that in mind when I pick up the alcohol, Ben. Thanks!

 

@FMod

 

That’s interesting because I’ve read some claiming that spreading can lead to air bubbles and an uneven coating. Of course, looking at the previous factory job, it would seem that this was the method they used as well… that is to say the compound looks to have been spread rather than pressed. These folks seem to agree with you too so I’m going with that idea I think.

 

I was considering using Arctic Silver 5, any objections to the product?

 

 

 

Funny thing is, this whole thing started because my GPU was getting too hot for comfort and now here I am fussing with my CPU :rolleyes:

Edited May 4, 2012 by TheFourthHorse

[FMod]

Arctic Silver 5 is seriously old. It's just not on par with modern ones. It loses 3 degrees to MX-4 and 1 to Zalman STG-2, if applied professionally. Due to being harder to apply, it will lose more. Only use it if you don't have to pay for it.

 

Coating shouldn't be even, the job of thermal grease is to fill in the gaps, metal-to-metal contact is still better. There may be some small air bubbles if not done right, but they don't matter if you have better contact elsewhere instead.

 

 

Funny thing is, this whole thing started because my GPU was getting too hot for comfort and now here I am fussing with my CPU :rolleyes:

Try downvolting your GPU. Way back I had a GTX 285 that didn't overclock at all (zilch), and it was noisy like all high-end cards and hot in the summer... until I found out that you could downvolt it by 0.2 mV (1.1 to 0.9) without dropping the clock at all. That's a 33% reduction in power consumption, so I could slow down the fan to keep it whisper quiet. All by just tweaking the voltage.

 

Most GPU will downvolt about 10%, it's not as much, but still a 20% reduction in power and heat.

They intentionally set higher voltages than necessary to reduce the number of potential RMAs. Only a couple percent of GPU are bad enough to actually need that voltage (and another percent needs even more).

Edited May 4, 2012 by FMod

[TheFourthHorse]

Good to know, thanks.

 

Hmm might look into the GPU thing... the 9800 is a dust trap and not very good with heat to begin with anyway. At this point I'm just holding its head above water until I can afford to upgrade to the 560ti.

Edited May 4, 2012 by TheFourthHorse

[FMod]

Oh. Then you're out of luck, 9800 series doesn't support software voltage control.

Still keep it in mind for the future. Unlike overclocking, downvolting is not only completely safe, it actually extends component lifetime and reduces the failure rate. The only reason not to downvolt a CPU or a GPU is if you're overclocking it, since you have to pick between the two.

 

Reducing the power draw is particularly relevant to Geforce cards, which suffer from two common failures, GPU's soldering fracturing from repeated thermal stress and power converters failing, both caused by power-hungry GPUs being placed on skimpy PCB designs.

 

For a new card, forget 560Ti, it's yesterday's news. What you'll be looking at is probably HD 7850, which is faster and only a bit more, or upcoming 7830, which should be about the same. They keep discounting the prices on older cards to keep up price/performance, but new ones are 28nm rather than 40nm, drawing less power with less heat and noise. New midrange Nvidias unfortunately won't be coming out for a while, they made a few mistakes with GK100 low-level design that cause poor yields until redesign is completed.