Well, after lapping my HS last night, I've had this nagging little voice in my head telling me to do the same from the CPU. I did the job totally with 800 grit sandpaper. Initially, I told myself I'd just buff what's there right now just to see if it's level. After about 30 laps in one direction and 30 in the other direction I discovered I had quite a concave IHS. So I just kept at it. Two 9x11 pieces of 800 grit later paper later I was left with a darn flat layer of copper looking back at me.

I was very happy to see that it lowered my temps doing the samex264.exe encoding test I have been using to benchmark them. Below are the numbers some of which you may have read in the thread I started about the heat sink last night. By the way, these numbers are my Q6600 @ 9x333 and as the caption in the image says, they are averaged over the entire encode:



The one thing that still has me a little miffed is the difference between the two dies (Cores 1/0 and Cores 2/3). Either there is something internally that's off perhaps related to the HIS (which I’m not going to remove so don’t suggest it) or the sensors aren't placed symmetrically and I’m being mislead. Oh well.