markintosh13
[H]ard|Gawd
- Joined
- Jan 7, 2006
- Messages
- 1,092
My e4400 Core 2 Duo cpu was running hot - overclocking to 3.33ghz required 1.4875 vcore for stability (12 hours of small FFT Orthos). Idle temps were 27C and load temps were 65 - 67C. I had previously lapped an AMD 4000+ with reasonable results, and anaconda's lapping of his Q6600 inspired me.
The bottom of the Arctic Cooling Freezer 7 Pro showed signs of hard contact with the edges of the cpu integrated heat spreader, and more paste than usual was required for good even thermal paste spread - a sign of a concave ihs... something confirmed with a razor blade. Not good - a concave heat spreader cap = bad heatsink contact = high temps.
So I decided to lap it. A visit to an auto supply store and $5 provided a sheet of 800 grit sandpaper, one of 1000 grit and one 1500 grit sheet. You decide on your lapping technique - I went with repeated movement in one direction, a few 90 degree rotations in the early stages, then primarily in one direction with no rotations for the finish.
I started by taping the 800 grit to the glass of an 8x10 photo frame and took a few swipes:
Note the copper starting to show through the top tin plate of the heat spreader cap... but only on the edges.
A few more swipes... there goes the warranty...
Ayup... that sure is concave.
After a few minutes:
After 10 minutes... it's flat.
A few minutes with 1000 grit and a few with 1500 grit and it's fairly mirrorlike - I didn't bother with ultra smooth and shiney, the goal was "flat":
Results:
Previous idle temp of 27C is now... 21C
Previous load temp of 65 - 67C is now... 54 - 57
Coolbeans.
The bottom of the Arctic Cooling Freezer 7 Pro showed signs of hard contact with the edges of the cpu integrated heat spreader, and more paste than usual was required for good even thermal paste spread - a sign of a concave ihs... something confirmed with a razor blade. Not good - a concave heat spreader cap = bad heatsink contact = high temps.
So I decided to lap it. A visit to an auto supply store and $5 provided a sheet of 800 grit sandpaper, one of 1000 grit and one 1500 grit sheet. You decide on your lapping technique - I went with repeated movement in one direction, a few 90 degree rotations in the early stages, then primarily in one direction with no rotations for the finish.
I started by taping the 800 grit to the glass of an 8x10 photo frame and took a few swipes:
Note the copper starting to show through the top tin plate of the heat spreader cap... but only on the edges.
A few more swipes... there goes the warranty...
Ayup... that sure is concave.
After a few minutes:
After 10 minutes... it's flat.
A few minutes with 1000 grit and a few with 1500 grit and it's fairly mirrorlike - I didn't bother with ultra smooth and shiney, the goal was "flat":
Results:
Previous idle temp of 27C is now... 21C
Previous load temp of 65 - 67C is now... 54 - 57
Coolbeans.