Check my sig for system specs.
With my older machines (much lower GHz, same Keypower PS), I was able to use junk power supplies to power the machine in my house (wire from yellow on the house ps to +12 on Keypower).

On this new machine, that method doesn't seem to work. Everything blinks on for a second then everything shuts off. I'm using the ATX jumper trick on the household power supply, so I unplug it momentarily, and nothing. Wait 2 minutes, plug in, blink on then nothing. (internal fuse blows, I guess)

I've tried this with 3 power supplies. When I plug each one into the mobo and other devices in the carputer, they all work fine.

So, what's happening?
My slightly educated guess is that the yellow wire I connect to on the house ps is connected to one +12v rail, which isn't enough.

So, how to fix this?
Is there a way I can bridge rails? How can I tell which yellow wires connect to +12v rails? And could the problem lie in trying to force that much power through tiny 14 guage wires comming out of the ps? Should I spend $$$(!) on a dedicated (high-amp) 120V to 12V converter?