I don't know if you can disable the power switch. It is probably an IC on the p/s motherboard. You might try opening it up and see if there is a jumper or something to make it AT-compatible. I've seen supplies with both AT and ATX connectors so maybe... But be very careful, the capacitors, etc. will have plenty of juice left in them if you just recently ran it (I zapped myself before on an old Atari ST p/s that had been unplugged for a week). If the p/s switch can't be disabled, I'd try a local computer recycler for an AT supply. Too bad I just threw out three AT supplies a month ago.
