Just because it didn't shut off doesn't mean it didn't get that hot. The temperature sensor doesn't actually touch the CPU and it takes a while for the air temperature to increase.
I think that the motherboard just cuts power to the CPU and kinda goes into a stand by mode where the fans are still on....... Because i had a machine over heat like that and it didnt completly shut down, just black screen....... Also AMD Athlon 64 chips are supposed to fry at 80C which is like 176F......
I just put half of a pea sized dab in the center of the cpu, dropped in the heat sink and tried to clip it. I took the heat sink out after dropping it in just to make sure I didn't have any of the compound running over the edges. It was a nice smooth circle splat in the center, not too close to edges but close enough that I know I'm getting a pretty good contact.
It's been hanging out at 35C. I've seen it at 34C too at one point.
This is assuming I use the PC for a while, 20 min, half hour, etc... then I restart into bios and check it out quick. I don't know if you would consider that idle considering the amount of time I was on it before, but meh. That's what I found out.
What's the name of that program that allows me to check the cpu temp within windows without going into bios?