If you can trace which wires from the power-switch button go to which pins on the motherboard, you can either pull the leads off the motherboard (after taking a note of where they go back :wink and check the switch+wires with a torch-bulb and battery, continuity-meter or multimeter.
Failing that, try bridging the motherboard connection pins with a short length of wire for a second or so. Take care NOT to contact any other nearby pins though, that could easily end in tears :upset:
I usually, when building/testing scrap systems, just grab a 3mm straightblade and short the 2 switch pins.
If it still doesn't turn on, unplug the 20 pin connector, and short the green wire to ground (make sure you're insulated from any metal or wires) while the PSU is plugged into a load, and see if it kicks on.
Allo mtbhank and welcome to TSF:wave: A couple of things to mention....
1} - Please read the forum rules about posting and start a new thread, rather than adding to an old thread that's already been solved.
2} - Your question should really be asked in the hardware forum, you'll have a lot better chance of an answer than in the 'Case Modding' section :wink)
3} - Without the specs to your PC, you don't really give us a lot to work with to finding a possible cure, although my 1st suggestion would be to look at your Power Supply Unit - It might well be 'on it's last legs' :smile:
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