Did you, at any point remove the CPU? If yes then buy some new thermopaste-diddly ( Don't know how it's spelled in English ), remove the CPU and the heatsink and clean every single remain of the old thermopaste from the CPU Socket. Then reapply the new one and reassemble the whole thing. BTW It's near X-mas so you can spend some $$ on water cooling but what I'd suggest is a new PC with a Core i7 920 D0 - that's what Im in the middle of building and it's VERY darn good.