and I may have broke it.
OK, replacing a power supply in my computer. The fan on the old power supply was dead/dying, so I got a new one. This one.
It is a 20+4 pin ATX unit.
This is were I screwed up. My MB is a 20 pin, so I unattached the extra 4 pins. Well... that 4 pin connector is the same as the 12v 4 pin atx connector. I connected that one to the 12v in, instead of the right one (P9 I think?).
Plugged in and powered on the PS. The green led on the MB lights up. Hit the power switch, nothing happens. Not a blink anywhere.
Pull it apart, figure out what I did wrong, attach P9 as it should be. Plug in, green led lights up, power switch... nothing.
Break out the MM and check the power switch, and it's fine.
Guess maybe I got a bad PS, and hook the old one up (it worked, just had a bad fan). Same thing. Green MB led comes on, but absolutely no response with the power switch.
For the record, some other (stupid) things I did that may have hurt.
When I built this computer 2 years ago, I used some supplied plastic stand-offs to attach the board... they were ALL broken (the only thing holding the MB up was the video card

Re-attached my cpu fan.
Installed a PCI USB 2.0 card.
Any thoughts or ideas?
time to look for a new computer/mb?