I picked one up that was labeled "crashes while booting" or some such from the goodwill near my house for something like $20 some years back. Brought it home, and noticed that the water block got burning hot when it was turned on, and tubes feeding the radiator were room temp. I broke the water loop open and flushed it out, and a whole bunch of white crap came out of the block. So, whatever the coolant apple shipped with it, was clogging the block. Reassembled the whole thing, had a terrible time getting the air of the system, but in the end it ran pretty good for a while until I left it off for a few months, and it refused to boot. In an act of desperation I hit it with the heat gun and that magically fixed it for a few weeks, and it did the same thing like a year later when I tried to boot it again.

I ran some benchmarks on it to compare with a POWER4 I also have, and yah lots of clock, shitty IPC. It was really cool in 2001, but by the time apple was putting them in mac's they were pretty terrible in comparison to the amd/intel's.