I hit it with a heatgun and there was no need for knife. And that was after it had been turned on.

Also, did you coat both IHS and Heatsink w/ paste? Given these things don't always wreak of quality like an Enzo, that might not be a bad idea.

Also, what kind of temp decrease did you see? I didn't get much until I added a small 40mm 5cfm fan on top...that gave me a 7C drop.