graysky, I think it's far more likely that you don't have good coverage of TIM, or your mount is too loose.

Also, if you see retention bracket marks in the HS now, how could it not have touched the retention bracket before lapping?

C2D's are -famous- for being concave, which requires lots more TIM. Put a -thick- line of TIM on your cpu, pointing from one side of your case to the other (IE, up and down, if you have a tower case), and see what your temps are.

Also, to verify, this thing does -not- use plastic pushpins, right? -Everybody- mismounts pushpins, they take lots more pressure to mount than you'd think.

It's a shame you bought another one... see if you can return it without a restock fee, else ebay it. There's no reason you can't get great temps after lapping. At -worst- you'd make the heatsink convex, which should work -better- on a concave C2D.