I have a spare PSU, the one I wanted to use, but I expected this kind of question,
so I took my PSU from my "old" computer, a Q6600 with SLI 8800 GTX, 4 HD SAS 15k in raid 0 with a specific card controler,
2 other HD 1To, and yes it still works with (I've just try!)
To power On with a jumper, or a screw driver, you just have to make contact between PW+ and PW-
So before making the photo, I have (of course) tested it inside the case, with all the correct casing wires, with the new PSU, and with the old (but surely working) PSU...
Memory contact seems perfect!