Normally pushing the switch means the motherboard sends a 3.3v signal down the white wire, which switches everything on - if I can pinch a 3.3v standby from the psu then I can use a toggle switch, ideally I'd use the original switch but I can't see how that's possible. Worst case is I have to drop a 5v standby signal down to 3.3v and send this back up the white wire via a toggle switch.
Anyway this is a bit of a long shot, but if anyone's got a (simple!!!!) suggestion for turning on the psu without a motherboard connected to it I'm all ears.
It may well be a non-starter, in which case I'll just bodge separate 5v and 12v supplies into the case, but I like re-using stuff.
