The machine that goes *boing!*
About five years ago, while I was in the middle of being unemployed, I traded some PC hardware for the processor board out of a rev. B Apple iMac. I'd read some of the "how to salvage your iMac after the stupid power supply sheds its container" articles and thought it would be a fun was to get a non-Sun non-intel machine running on my home network.
Well, this grand idea went nowhere and the iMac rotted away in the project pile, only emerging once when I worked out the power supply pin assignments, until this fall when I cleaned out my workroom and started working on building the glowy server case. The glowy server case cleared enough layers away so that the iMac processor board rose to the top, and I dug out my list of pin assignments and started assembling the power supply adapter.
After a few mishaps (I had also grabbed some howto pages off the net, and managed to start wiring the processor board connector with the power filter board pinout. I cut that connector off, then broke off a pin on the ATX side of the connector when I was re-stripping the wire ends. And when the ATX sockets I ordered came in, I mislabelled the pins and wired the ATX connector backwards, so I had to cut that end off and solder in a third socket with the correct wiring. And after I did that, I accidentally connected +5VSB to ground while I was checking the circuit and ended up killing the ATX power supply (I'm not sure why I wasn't using one of the junk big-box power supplies that litter the basement, but I suppose I have to sacrifice useful hardware every now and then to preserve my reputation as Death of electronics.)
But after all this, I got the power cord all wired up (including the little circuit that converts the iMac +5V PWR-ON to the ATX 0V PWR-ON signal,) attached it to another junk power supply and an Apple->VGA monitor converter, pressed the power button, and watched the cpu fan spin up and the processor board power light turn on. But nothing showed up on the monitor (which wasn't that surprising because I've never been able to get any Mac to put a signal through that horrid thing. And without the little sad Mac face (or whatever Apple put on their powerpc machines) I couldn't be sure that the thing was actually booting or if I'd managed to lobotomize the machine and all I was seeing was the hindbrain reacting to the presence of power on the +12V pin.
No disk, no blips of activity on the cdrom drive, nothing to indicate that there was anything here aside from an inefficient resistance heater. Except, maybe, for the headphone jack. I scampered upstairs, grabbed my headphones, plugged them into the (not marked, because this iMac is sans case) headphone jack, and pushed the power button. *boing!*
Sounds like victory to me. Now I need to wire VGA to Apple video connector and then I'll be able to actually see the poor little sad Mac face.
Update: I plugged a cd-rom drive into the box and dropped a Slackware linux cd into it. When the mac boots, it attempts to read stuff off the cd, then sits there glumly and lets me turn it off by poking the power switch lines on the motherboard. If I could actually see what it's doing, I'd be set.