Polishing heatsink necessary w/ thermal compound?

[DonNiggera]

I read somewhere if you lap your heatsink (with 2000 grit sand paper) you can decrease your temperature 5C! Would it help like this even with artic silver 2 applied?

 

[Squibby]

While the 5C thing is probably a little overstated...just like ACII's effect is...it couldn't hurt. Lapping the heatsink not only slightly cleans off the connection, but it also gets rid of some of the "microscopic valleys" that the Arctic Silver is supposed to fill.

Anyway, the difference will probably be less noticable with ACII, but as I said before, it couldn't hurt.

Squibby

 

[pcFun]

don't know about ACII and your HSF. But I just did it to the
Volcano II w/ 150 followed by 300 grit. It surprised me by
lowering cpu temp on the 1.2 Athlon by 4c on full load w/ Radio
Shack's thermal compound.

The cpu runs around 40c regular load and 33c idle now, that's
5-6c lower than before.

I think those "microscopic valleys" are what keep thermal
compound in place right on top of cpu, otherwise most thermal
grease is "pushed" aside by the pressure from HSF clamps.

 

[TunaBoo]

As long as your HSF is smooth, do not lap.


Flatness is what matters 90% of the heat transfer. Smoothness helps a little, but if you do not lap it PERFECTLY flat, then you will decrease preformance. AS does a good job of filling holes between HSF and CPU, let it do ites job. Just make sure the mofo is flat and free of dents and foreign material (like tims)