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View Full Version : Why not use more thermal grease?


sillyeagle
12-28-06, 11:52 PM
I always see the recomendation of a "BB" sized amount and let it spread on its own, but when using a BB sized amount it only spreads to a smallish area in the cetner of the heat spreader. So I am wondering why not use a bit more, like twice that amount, so that the edges of circle of grease are pushed up near the edges of the heat spreader? Seems to me the more surface area to have optimum thermal transfer the better off you are.

When I put this latest system together I made sure to to get as much coverage as possible, and it seems to have had positive results, as I'm getting a great overclock with awesome temps.

Roadhog
12-28-06, 11:53 PM
I always see the recomendation of a "BB" sized amount and let it spread on its own, but when using a BB sized amount it only spreads to a smallish area in the cetner of the heat spreader. So I am wondering why not use a bit more, like twice that amount, so that the edges of circle of grease are pushed up near the edges of the heat spreader? Seems to me the more surface area to have optimum thermal transfer the better off you are.

When I put this latest system together I made sure to to get as much coverage as possible, and it seems to have had positive results, as I'm getting a great overclock with awesome temps.


You want to coat the CPU in a THIN THIN layer of the stuff, screw the BB size in the center.

If you use to much, it acts as an insulator.

jAkUp
12-29-06, 12:10 AM
Yea, basically enough to fill the microscopic gaps in the heatsink and CPU shim... I usually use a very, very thin coat on the entire heatspreader.

Roadhog
12-29-06, 12:15 AM
Yea, basically enough to fill the microscopic gaps in the heatsink and CPU shim... I usually use a very, very thin coat on the entire heatspreader.


I do that, but take it a step further, Put it on the heatsink also then rub off most of it.

LORD-eX-Bu
12-29-06, 12:21 AM
I rub some into the heatsink and the cpu and clean it off... then I put a small dot in the middle and rotate the heatsink on top of it to spread it then without taking it off I clamp it down or screw it in whatever... works fine :)

superklye
12-29-06, 12:32 AM
-LORD-eX-Bu']I rub some into the heatsink and the cpu and clean it off... then I put a small dot in the middle and rotate the heatsink on top of it to spread it then without taking it off I clamp it down or screw it in whatever... works fine :)
That's a damn good idea. I spread it with a razor and usually end up getting it all over my fingers because I'm holding the CPU in one hand, spreading with the other. (mikec)

Roadhog
12-29-06, 12:35 AM
That's a damn good idea. I spread it with a razor and usually end up getting it all over my fingers because I'm holding the CPU in one hand, spreading with the other. (mikec)

I put the thermal paste on after its in the socket... silly you :P

Vanzagar
12-29-06, 03:22 PM
I end up spreading it around with my tongue, but then it starts filling up my ears...

ViN86
12-29-06, 03:29 PM
I always see the recomendation of a "BB" sized amount and let it spread on its own, but when using a BB sized amount it only spreads to a smallish area in the cetner of the heat spreader. So I am wondering why not use a bit more, like twice that amount, so that the edges of circle of grease are pushed up near the edges of the heat spreader? Seems to me the more surface area to have optimum thermal transfer the better off you are.

When I put this latest system together I made sure to to get as much coverage as possible, and it seems to have had positive results, as I'm getting a great overclock with awesome temps.
thermal grease is used because it has a lower thermal resistance than air. therefore it fills the gaps between the CPU and the heatsink to decrease thermal resistance. however, direct contact between the heatsink and CPU offers lower thermal resistance than having thermal paste at the interface.

so, its best to use as little thermal paste as possible to fill the small (practically microscopic) gaps between the heatsink and CPU and adding to much actually increases thermal resistance, increasing CPU temperatures.

i could user some cool looking formulas and thermodynamics to explain it, but i think i did a good enough job already :)
Yea, basically enough to fill the microscopic gaps in the heatsink and CPU shim... I usually use a very, very thin coat on the entire heatspreader.
yea, what he said.

ynnek
12-29-06, 04:50 PM
last time I read artic silver's website, they claimed the best way to spread it (unless you have their really old formula) was the small dab in the middle, mush, and then slight twist technique.. They claimed it was the best way to get an even coat with minimal air pockets.

So I follow them.

I bet there's probably a better way, like how some of you mentioned up above, but the chances of messing up the thickness or getting too many air bubbles are probably much higher.

stevemedes
12-29-06, 05:09 PM
I do that, but take it a step further, Put it on the heatsink also then rub off most of it.

qft, i believe that method is called "tinning" the heatsink.

sillyeagle
12-29-06, 05:25 PM
last time I read artic silver's website, they claimed the best way to spread it (unless you have their really old formula) was the small dab in the middle, mush, and then slight twist technique.. They claimed it was the best way to get an even coat with minimal air pockets.

So I follow them.


Yeah, and when you follow their instructions to a T you don't get that much coverage, which is why I am questioning what they have said.

SH0DAN
12-29-06, 05:34 PM
Yeah, and when you follow their instructions to a T you don't get that much coverage, which is why I am questioning what they have said.


And so you should,as I have found it depends on the HSF used,I used what they told me to on the web site and got sub par performance.Two weeks later I took the whole thing apart,and re-did the AS5 application,I used twice as much as they say to,and got much better temp readings.YMMV.

superklye
12-29-06, 05:35 PM
I put the thermal paste on after its in the socket... silly you :P
:mad:

SH0DAN
12-29-06, 05:47 PM
Kyle you can always use a piece of foam(a small foam block)to hold the cpu in while you apply the AS5.This is what I do sometimes,or as mentioned just lightly drop the cpu in the mobo socket,and then apply the AS5.

lightman
12-29-06, 06:07 PM
Kyle you can always use a piece of foam(a small foam block)to hold the cpu in while you apply the AS5.This is what I do sometimes,or as mentioned just lightly drop the cpu in the mobo socket,and then apply the AS5.

Well, given that the Core 2 Duo, using a 775 socket, has no pins, I'd say the foam block isn't a great idea ;) (xmasgrin)

I'm with Roadhog on this one, though. Put the grease on the chip after you put it in the socket (xmasmile)

grey_1
12-30-06, 07:25 AM
Yeah, and when you follow their instructions to a T you don't get that much coverage, which is why I am questioning what they have said.
I do what the guys are saying too. I followed AS's instructions and ended up redoing it a few days later, with a credit card edge. I do the heatsink using a plastic bag over my finger and wipe it down til the copper just looks stained, but not coated.

Dazz
12-30-06, 07:47 AM
I put the CPU in the socket place a small amount of paste on the CPU use a old credit card and spread it out, use an old rag and clean up the sides then place the HSF on twist a little then lock down the HSF.