Originally Posted by graysky

Originally, I just used 800 grit paper (you can read about it in the other thread started by me entitled 'lapped my q6600 today') but I was getting a little nervous about taking off too much material and stopped before the CPU's IHS was totally flat and before all of the nickel plating was removed as you can see in the pic in that thread.

Yesterday, I finished the job and put a mild shine on it with a sheet of 1000 grit I got from the local auto parts store just for the **** of it. The temps have improved a little by removing the extra material (my IHS was pretty concave). Also, the temp difference between the cores has improved quite a bit which really underscores the fact that the concave IHS was causing unnaturally high temps. I know I can lap off more material to get it even flatter, but I'm happy enough with the decrease this gives it.

Here are a few pics and the temp. results I got from lapping both my CPU and HS. I would recommend that anyone wanting the best $20 decrease in temps should consider lapping both the CPU and HS.

Q6600 @ 9x333 and stock voltage (lapped), Ultra-120 Extreme (lapped) with Scythe/s-flex SFF21F 1600RPM fan, P5B-Del, P182 case:

Temp results:


After about 5 minutes of lapping in each direction with 800 grit. You can see how the nickel plating has come off around the edges first which shows you just how concave this thing really was:


After more lapping most of the nickel plating has been removed expect in the really low areas (the camera flash fired so close to the chip makes all the scratches show up much more so than they do under normal light):


Switched to 1000 grit, here's the result:


Another angle shows the nice dull reflection, still very so slightly concave at the extreme edges, but good enough for me:


I would recommend that anyone wanting the best $20 decrease in temps should consider lapping both the CPU and HS.