I think it had something to do with the pin on the stock cooler. All of them were locked in, but one would always push down farther, then pop back up (not completely, but enough to make me think there was something wrong with it clipping in). I'm attributing it to that and the fact that it was stock. My friend has an intel core 2 duo 2.4, and he idles at 50c and loads at 60-63.
Back on topic,
GOW looks great, don't get me wrong, but Crysis (the demo) has really spoiled me graphically. Does anyone else agree?