Newbie to thermal grease :/

nobodythere

Just for the record, the last time I messed around with a heatsink, there was no such thing as thermal grease because nothing went past 25MHz:P

I'm trying to put a fan controller in a Prescott 3.2, and have to take off the heatsink to put in the temperature sensor.

Long story short, I ended up having to take the heatsink on and off 3 or 4 times before getting it right, and reapplied the thermal grease each time (because it stabilised around 95 degrees celsius if I didn't :eek: ), but now after so many attempts it is overheating. The surfaces have been cleaned with dry tissue. Is there anything else I should clean it with, because the surfaces don't look too shiny and we're all out of tissue!

TimTim

I used a tiny amount of white spirit and cotton buds to remove the thermal paste from my cpu and heatsink, my pc is still working. Although I didn't let it spill off the top of the cpu.

Sgtshaft

grasshopa wrote:

The surfaces have been cleaned with dry tissue. Is there anything else I should clean it with, because the surfaces don't look too shiny and we're all out of tissue!

Christ!!! dont clean it with a tissue, clean the surfaces of the chip die or core using a solvent such as high-purity isopropyl alcohol or an acetone.

Cleaning your CPU/heatsink is an important step during the installation of your CPU/heatsink. Contaminants like old, dried, or less effective thermal paste or finger oils can reduce the effectiveness of your new paste. Lint, hair and dust can reduce surface contact and adversely affect heat transfer. Remember, on some CPUs the contact surface is only the size of a your fingertip, so the contact between surface areas is extremely important.

No matter what paste you are using, try putting just a small amount on the CPU die. For smaller Athlon XP and Intel CPUs you really only need something like the equivalent to half a grain of rice.But start off with as little as you think would give a super thin layer. It's always better to have too little to start

Using something with a clean edge, spread the paste out across the whole of the die. Most people use something like a credit card, stiff business card, or razor. Make sure not to scratch the surface if you use something sharp!!!

Nukem

More is less. Try using a laser/bank card or the sort. Use my Game card now,bout the only use it gets.
Try get the smallest amount over the whole thing so you give it a good bond but better conductivity over a shorter space.

Nukem

SickBoy

grasshopa wrote:

Just for the record, the last time I messed around with a heatsink, there was no such thing as thermal grease because nothing went past 25MHz:P

I'm trying to put a fan controller in a Prescott 3.2, and have to take off the heatsink to put in the temperature sensor.

Long story short, I ended up having to take the heatsink on and off 3 or 4 times before getting it right, and reapplied the thermal grease each time (because it stabilised around 95 degrees celsius if I didn't :eek: ), but now after so many attempts it is overheating. The surfaces have been cleaned with dry tissue. Is there anything else I should clean it with, because the surfaces don't look too shiny and we're all out of tissue!

Ok, I may have misread your post and if I have sorry but do not put the temperature sensor between the CPU and heatsink!
If this is what you're trying to do then the CPU is reaching 95c because of bad contact and throttling to save its life.
Run this program and it will show you the CPU and throttle status of your prescott.

nobodythere

Thanks for the replies, you're right about the thermal thing. Doesn't matter about it anyway because it doesn't fit under the processor, so I'm just gonna leave it turned off.

I went to the chemist and the best I could get were wipes with 70% isopropyl alcohol. I re-greased it and the CPU starts at about 45 degrees which I assume is OK by today's standards. But watching it in the BIOS has brought it up to 70 degrees at which point I got scared and turned it off...

Is this due to bad greasing or other factors? there are about 11 fans in the case by the way

mp3guy

you've got a fan on the heatsink, Right?

nobodythere

Right! Stock Intel fan, and 4 thermaltake fans around it

mp3guy

you've taken the thermal pad off the stock HSF before adding your own, Right?

nobodythere

Came to me already sealed on, removed it to put the thermal sensor under it. I'm guessing thermal pad means some kinda sticker that comes on the heat sink? Yes I took that off

mp3guy

well, under THAT sticker theres a layer of grey paste, that should be removed before using your own thermal paste.

nobodythere

yeah, I had two clean (relatively :P) metal surfaces before I greased it.

mp3guy

hmm, i'm stumped then... all i can think of is make sure you're clamping it on properly

astrofool

grasshopa wrote:

Came to me already sealed on, removed it to put the thermal sensor under it. I'm guessing thermal pad means some kinda sticker that comes on the heat sink? Yes I took that off

as said above, do not put thermal sensor between the chip and heatsink.

nobodythere

All sorted, noticed that the circular space on the heatsink was smaller than the processor so I put some grease outside of it. Prescott 3.2 stable at 54 degrees, is that anything to worry about? Last time I built, alarm bells would be ringing at 40

Sgtshaft

grasshopa wrote:

Prescott 3.2 stable at 54 degrees

Is that when the CPU is idle? If so, stress the CPU a bit and see how high the temp goes, d/load Prime95 and run the torture test.

nobodythere

Yes this is idle, but what more can I do? It's got 11 frickin fans in it!!!

Sgtshaft

Is it a stock HSF? If it is go buy a better one I cant recommend one as I am a AMD fanboy

nobodythere

I'm not sure if it's the stock HSF, but the fan does say Intel on it...

kasintahan

Where are you putting the thermometer?
Don't tell me it's between the die (chip) and the heatsink...

Wipe off the heatsink and die (careful).

Apply the thinest layer of thermal compound to the heatsink.
REMEMBER - it's the heatsink that does the cooling, not the compound - the compound is just there to ensure a good seal.

Place the thermometer close to BUT NOT ON the die.

Lower the heatsink onto the die and lock in place (AMD cpu's are a bit trickier with their catches).

Max CPU temperature should be about 75 degrees under load. But the CPU is good to around 90 degrees after which it will shut itself down (on modern CPU's).

zuma

Im unsure about Intel chip but if my AMD64 3000+ gets close to 50C under load I get scared!!!

Stephen

Intel prescotts are notoriously hot running - 50 under load is pretty good for one of those, but that's what he's getting at idle, dunno what a normal idle temperature for one of those is.

My A64 (venice/s939) only gets to about 43 degrees under load, which is nice when compared to my old athlon xp's which used to idle around 50 too

stevenmu

Sounds like you could be having a similar problem to one I had recently. I was fitting a new zalman and I tried using the bracket that came with the motherboard. This wasn't pressing the heatsink down hard enough against the CPU and I was getting crazy temps, 23C idle and shooting up to beyond 70C (I chickened out at 70, I thiink it was going higher) under even a light load.

Like the guys said, make sure both the heat spreader on top of the cpu and the contact are of the heatsink are completly clean (maplins sell bottles of Akasa TIM-Clean, which is a citrus/petroleum based liquid that gets the grease off really easily, altough some people say you shouldn't use citrus based products as they leave a residue.). The use a credit card of similar to spread as thin a layer as possible on the cpu. When you're putting the heatsink on, make sure it just goes down straight and doesn't slide, rubbing off any grease. Also make sure it clamps down very tightly according to whatever instructions came with it. I've no idea exactly how hard they should clamp or screw down, but it's certainly hard enough to make me feel very incomfortable doing it.

Raz

I think your problem might possibly be the number of fans yo have in the system. 11 is a huge number, it must sound like a small tornado!
If you have the fans posititioned so the air flows are crossing you could be creating a dead zone ie. no air moving at all around the cpu.
How have you got your fans set up?