Well I got the BUW12A transistor and installed it but still no dice, I press
the power button and the relay clicks, green light comes on, and it makes a
soft whistle sound, then the relay clicks again followed by the orange and
red lights coming on too. I never see a peep out of any of the PSU outputs
except the 12v standby.

I thought I checked every single semi on the whole ps board, but maybe I
missed something. What else should I check?