Setting up the family computer, with stock cooling. It's a Tbred B 2400+ (a nice overclocker but they won't let me loose, wise of them
). Got the heatsink/fan on, put the board in the box, hooked everything up.
Switched the system on and suddenly heard a high-pitched screetching from the CPU socket area. Being the antsy person that I was I killed power at the back panel quickly, took out the AMD stock fan and did some adjusting.
It turns out that (somehow) something from the CPU carton had got into the fan, gotten stuck, and prevented the fan from running up.
Aforementioned Tbred B survived the passive cooling test with flying colors and is happily folding away.
I've also fried a Thunderbird. It, too, was folding away, and suddenly the substandard ex-Compaq heatsink fell off (i was running on a tight budget at the time, waste not want not) and the CPU core went critical before I could shut her off. I had to shoot some Halotron on it.
Moral? Always use Socket 462 heatsinks with either screw holes or three-prong clips.