Speaking of stupid computer tricks, I recently was asked to looked at one of my dad's friend's PCs. He said that "the motherboard had been replaced before" and that he "thought it went bad again." With no more info than that I opened the case, first noting that it said PIII 866MHZ on the front. First, not only the motherboard, but the also the CPU had been replaced with some Athlon CPU, probably in the 1900+ - 2600+ range, using, of course, the retail HSF. I also noticed that the only fan in the case, which was only designed to cope with the heat of a PIII, had been removed.

The CPU was, of course, fried. I'm surprised it lasted as long as it did on passive case cooling.