applying new thermal paste?

[CallMeMike]

Hello.

I've been getting temps too high for my dual core AMD 64 bit cpu and want to bring it down some. I've just bought a new chassis with better airflow and a Zallman heatsink/fan combo, along with some arctic silver thermal paste.

When I installed that processor, I just used the stock fan that came with it, and of course the paste was already applied. What I'm wondering is, what measures do I need to take before applying the arctic silver to it? Is it just a matter of wiping off the old goop, or do I need to do clean it off better? If so, how - is there some sort of chemical I need to treat it with, or doesn't it matter?

it's been in use for around 8 months now, so I imagine the stock paste it came with is pretty well soaked in by now. I'm hoping it's not too late to switch to something else and get better results.

Thank you much.

[oralpain]

Honestly, just swapping thermal paste probably won't get you a noticeable temp improvement. The stock shin-etsu pad is not that bad.

Anyway, you'll want to get all the old paste off, and be left with totaly clean, residue free, bare metal, if you want the best possible performance. Clean the CPU and heatsink with whatever you like, then clean that off with high purity isopropyl alcohol.

To apply the new paste, just put a dab the size of a grain of rice in the center of the heatspreader and clamp the heatsink down.

[IAmGhostDog]

then clean that off with high purity isopropyl alcohol.

Coffee filters work really well for that.
They're lint free.

[Mjölnir]

Coffee filters work really well for that.
They're lint free.

That's good to know Medical gauze is also a good option. Sterile and lint free.

The biggest factors in cleaning a surface is that the surface needs to be sterile and dry, plus it needs to be close to pH neutral.

Isopropyl and Ethyl alcohol are pH neutral (or very close to it). In addition they evaporate quickly, hence their use as sterilising agents. Additives to these products typically don't evaporate well, which is why higher purity is best.

If you can't get your hands on high purity isopropyl or ethyl alcohol, methylated spirits wouldn't be a bad alternative. The downside is that it doesn't evaporate as quickly as alcohol and can result in some solvent being left on the surface, so the idea is to wipe it off before it can dry on the surface and probably rinse it with demineralised water. It never hurts to rinse with demineralised water (just don't dunk it). Use a damp piece of lint free material and wipe it dry immediately after.

When you wipe the surface, don't use the same part of the material twice. That would just smear what you just wiped off back onto the surface, defeating the purpose of your question. Also when you do clean it, do it twice.

Arctic Silver offer the ArctiClean kit which essentially is two parts. A common cleaning technique with part one as an acidic solvent (ArctiClean 1 = pH 5.2) and part two (also a solvent) as a neutraliser (ArctiClean 2 = pH 7.6). I use a more powerful combination of Phosphoric Acid and Ammonia water, rinsed with demineralised water (though I don't claim that it's more effective).

[CallMeMike]

Thanks for all the suggestions, I do appreciate it!

I'm pretty sure it's not because of the thermal paste that I'm getting high temps. The case I bought for this PC when I built it just turned out to have a bad design. Too many gaps for dust to accumulate, not-so-great fans, and the design made it very difficult to prevent the cables from impeding the airflow through the 120mm fan in the front. When I added an nvidia 8800 GTS to the mix, the temps inside became worse, and I imagine that affected the cpu too.
Well, I got a Cooler Master chassis now, and I think it'll be alot better for airflow, plus the Zallman heatsink/fan. I figure it's probably not a good idea to remove the old cpu fan without replacing the paste, so I got the Arctic Silver.
I didn't know Arctic Silver made a cleaning kit, I'll have to check that out.

Thanks again.

[John C]

Isopropyl alcohol works great for cleaning the CPU's, and leaves no residue, which is very important. Make sure you get the 91% or better, not the 70% variety (the 30% is water). And dont get "Rubbing Alcohol", it usually has lanolin added, which is not good. You dont need a moist and soft CPU!
The Iso is available at any supermarket or drug store, usually under a dollar for a bottle, which will last a long time. It should be standard in every computer geeks toolbox. Great for cleaning almost all electrical contacts as well.

[Mjölnir]

Isopropyl alcohol works great for cleaning the CPU's, and leaves no residue, which is very important. Make sure you get the 91% or better, not the 70% variety (the 30% is water). And dont get "Rubbing Alcohol", it usually has lanolin added, which is not good. You dont need a moist and soft CPU!

Not a good idea to assume that the 30% is water. Many Isopropyl products contain some (other) form of disinfectant and in some cases they include some form of moisturiser - among other things - both of which will leave residue. Demineralised water isn't a bad thing, provided that you wipe the surface dry and give it a short while to ensure that it's fully evaporated (it has no foreign agents like bacteria and is pH neutral). At least it'll help remove any other chemicals that are left behind after the alcohol evaporates. That's why I suggest to rinse the surface a couple of times with demineralised water.

If you do find a lower percentage Isopropyl Alcohol solution where the remaining percentage solely consisted of water, that'd be almost as good as 100% Isopropyl Alchol, save for the fact that it won't evaporate as quickly. You just give the surface a wipe or wait a little bit longer and you're right to go. None of the solutions I've seen have this mix though, and believe me I've looked high and low.

[CallMeMike]

That's good to know, JohnC, thanks.

I do have some of the 70% isopropyl, which I do use for cleaning alot of things (it's especially good for guitar strings and frets) but I wouldn't have thought about the lanolin or other additives. I don't think I've ever seen 91% or better, but I'll have a look around the pharmacy and see if they have any.

[CallMeMike]

Where does one get demineralized water? Is that the same as distilled water?

[Mjölnir]

Technically they're not the same (distilled should also be demineralised), but for this purpose they're both sufficient

[curlysir]

That's good to know, JohnC, thanks.

I do have some of the 70% isopropyl, which I do use for cleaning alot of things (it's especially good for guitar strings and frets) but I wouldn't have thought about the lanolin or other additives. I don't think I've ever seen 91% or better, but I'll have a look around the pharmacy and see if they have any.

I buy 91% at Walmart in the pharmacy section. 91% is all I buy anymore. It was in stock the last time I looked a couple of weeks ago. You can get the pure stuff at Fry's, it is not cheap, around $8.00 for a quart when I bought mine.

[CallMeMike]

Thanks again, guys.

[CallMeMike]

Just a follow up here.
I did find some 91% isopropyl, and some distilled water, and used coffee filters, as suggested, to clean off the cpu heat spreader.
I've installed the arctic silver per the instructions on their site, and placed the Zallman heatsink/fan combo on the cpu and put all the guts of my computer in my new chassis.
That Zallman unit is HUGE (and sits about a micron from touching my RAM), and has a pretty cool green LED in it, though I thought it was supposed to be blue, like my fans are. Oh well, it's obviously doing its job.
It's been running now for about 20 minutes with this new stuff, and my CPU temp while typing this is fluctuating between 29C to 31C.

I'd say that's a vast improvement over the other day, at 49C right after boot-up!

Yes, I know it'll take a few days for the new thermal goo to really begin doing its thing, but even so, this is already MUCH better than the last time I opened the case and simply sprayed the dust out of the stock AMD heatsink and fan. I have yet to stress test it, but I doubt there will be any trouble with temps anymore.
IIRC, even "cold" and new and dust-free, with the stock AMD heatsink/fan, it booted up around 40C or so.

Thanks again, guys, for your help.

[IAmGhostDog]

I do have some of the 70% isopropyl, which I do use for cleaning alot of things (it's especially good for guitar strings and frets)

Just strings and frets?
I wouldn't recommend that on your fret board.
(click "Trio" in my sig)

[CallMeMike]

Rosewood fretboard.
No, I don't clean the fretboard with it, but use a cotton ball soaked in isopropyl and run it up and down each string, and an old toothbrush to get at the fret edges to clean the gunk out.
I haven't seen any damage at all to the fretboard, and I *am* pretty careful.
Doing this will actually clean the strings off really well, and reduce the uneven vibrations which result from fingerstuff buildup.