Best Thermal Grease/Paste?

[Black Label]

Definately be careful with it. And I don't recommend trying it with one that doesn't have a solid base...I tried it once with a copper core in the heatsink, then the rest was alminum or whatever it is. It didn't turn out well...
competition.

same here, i just tried lapping for the first time on a vantec aerocool that has a copper core and i fucked it all up. its all scratched up and its no where even close to a mirror finnish. i have to relap it sometime when im not to lazy

 

[ColinR]

same here, i just tried lapping for the first time on a vantec aerocool that has a copper core and i fucked it all up. its all scratched up and its no where even close to a mirror finnish. i have to relap it sometime when im not to lazy

Yeah, but remember, you only need to have a good finish where the hot part of the cpu (be it spreader ot core) contacts the heatsink.

 

[PsycoGeek]

Yeah, but remember, you only need to have a good finish where the hot part of the cpu (be it spreader ot core) contacts the heatsink.

Not true. If you only lap the center of the heatsink, or the heatspreader, you are just starting to remove the high spots and will not achieve a true flat surface until the whole thing has been lapped. Unless you finishe the entire surface you could leave a slight "dome" or bump on the contact area.

 

[PsycoGeek]

On the newer processors with the heatspreaders over the core is it really that hard to lap them anymore? Back in the day I remember people actually lapping the exposed cores very carefully, the heatspreaders seem like cake compared.

No it isn't. The P4 heatspreader is easy to lap. You just have to remember to protect the pins on the processor and do a very good cleanup job on it before putting it back in the socket. And don't forget to mark it so you know what it is...

 

[Warriorprophet]

Stars 350! Its better then AS2/AS3, and I just now ran out from what I got with my heatsink.

Maybe I'll try the PCM+ when I get around to modding this case so this watercooling kit I have siting here doing nothing can get some use.

 

[RLich8]

I like Arctic Silver 5

 

[ColinR]

Not true. If you only lap the center of the heatsink, or the heatspreader, you are just starting to remove the high spots and will not achieve a true flat surface until the whole thing has been lapped. Unless you finishe the entire surface you could leave a slight "dome" or bump on the contact area.

That's not exactly what I said. You need the classic mirror finish where the cpu touches the heatsink. It has to be flat here. There is no *requirement* for the whole of the underside of the heatsink to be mirror like. When you have dual material heatsinks, only the copper slug needs to be concentrated on. Getting them evenly shiny will be difficult due to Cu and Al having differing hardness. Focus on getting the contact area mirror smooth.

 

[PsycoGeek]

That's not exactly what I said. You need the classic mirror finish where the cpu touches the heatsink. It has to be flat here. There is no *requirement* for the whole of the underside of the heatsink to be mirror like. When you have dual material heatsinks, only the copper slug needs to be concentrated on. Getting them evenly shiny will be difficult due to Cu and Al having differing hardness. Focus on getting the contact area mirror smooth.

And what I said was...

The whole thing has to be lapped to ensure flattness. If you do not lap the entire surface you risk leaving a high spot in the center that may have a rounded or dome shape.

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The reason for this is because you are doing it by hand. You cannot controll the pitch of the heatsink by touch, and unless the entire surface is flat the heatsink will pitch (rock) back and forth as you move it across the sandpaper, thus leaving a "rounded" shape if you only lap the middle. You will never notice it rocking back and forth. It's imposible for you to detect. Therefore, for the best results, you must lap the entire surface to achieve true flattness.

Now, how to achieve this with a heatsink with two different metals... patience and a very light touch on the heatsink. I know, I've done it. You have to lap about twice as long with an Al/Cu heatsink. And you have to keep it lubricated with plenty of water, rinse the heatsink and paper frequently, and lap slowly. You will go through a lot of paper doing it, but it's not impossible to do.

If you don't beleive me, call a local machine shop and ask them. I got the advice from my father way back in the day. He was a machinest at Rockwell Int. (now Boeing) for 25 years.

-EDIT- I never said anything about a mirror finish. I was strictly talking about ensuring flattness for the contact area, which can only be achieved by ensuring flattness across the entire surface area of something so small. Machining can ensure flattness in such a small area, hand lapping cannot.

 

[_Korruption_]

even slks need a good lapp. the only heat sink that i have noticed that lapping is (maybe) truely optional is the zalman 7000 alcu. i felt that and it is damn smooth (dont mean it cant be made better)

Lapping without a instrument to measure flatness can cause negative effects on thermal performance. With smaller die surface CPU such as AMD XP, a properly lapped HSF could improve 2~4 celeius, however, we really do not recommended new PC modder to try this as our HSF base are measured 0.03mm in flatness within 4 corners when leaving assembly line.

I'd much rather have a flat base over a smooth base that isn't flat.

 

[ryuji]

I'd much rather have a flat base over a smooth base that isn't flat.

if you lapp it its going to be both smooth and flat if you do it correctly, as the second quote says as long as you do it slow and dont press down it should be flat