I'm in the process of building my first Takky, and I've got all the physical case modifications done (I've fit the wiring harness in the correct spot, lengthened the slots for the logic board, rewired a wiring harness, and I've performed the VGA modification to the analog board). I'm planning on using a Quadra 630 power supply as the PSU for the logic board and HD.
I wired it up dry last night. I pulled the 5v, 12v, and two ground lines from the analog board to the PSU from the PSU's molex connector. (So no power supply is coming from the A/B to the logic board. On the 630, these lines would have gone to a CD-ROM, so they can't be critical to the PSU's operation.) I connected my 630 PSU to my wiring harness (also from a 630 - aka the infamous "630 connector"). And I fit in a Q630 motherboard (I've got a 5500 board, but I haven't done the 3.3v regulator yet).
Anyway, I plugged the AC supply into both the A/B and the 630 PSU. Upon flicking the switch on the A/B, I heard the CRT charge up. I pressed the power button on the keyboard, and nothing happened.
The 630 supply is a soft-power switched supply. So it needs an ADB pin shorted to ground to start, right? How do all you geniouses get your 630 supplies to power up when the 630 PSU isn't connected to your Mac's ADB lines?
I tried shorting the ADB power sense line to ground on the 630 PSU, but that didn't do anything.
Can you all help? I can't figure out how to jump start my 630 PSU. And if I can't get it working now, I can't imagine how I'll get it working with a relay.
Also, can someone tell me which line on the wiring harness is supposed to carry 3.3v for PCI logic boards?