Ok, I have this same problem. My cpu isn't exactly overheating, but it runs around 65c while just doing normal stuff. I replaced the fan with a new fan:
Newegg.com - COOLER MASTER Vortex 752 RR-CCH-P912-GP 92mm Sleeve CPU Cooler
But it's still running around 65c while just doing regular things. Now it doesn't seem to be running much hotter while playing the game, but it should be cooler than the stock fan, correct? I tried to contact cooler master, but they don't answer e-mails and there's nobody on their live help links, so I guess I'm on my own, unless somebody can help.
When I put in the fan I used the thermal grease that came with it and put a dollop about the size of a quarter on the cpu and pushed the fan on, moving around and around a couple times. Unfortunately I can't see under the heatsink to see if it was oozing out or if there was proper coverage.
Rather than using the grease is there like a heat conducting pad that could be stuck on the cpu instead?
Let me know. Thank you.