When you get such a machine you start over. From the beginning.
You pull out the PSU and the motherboard onto cardboard with bare min parts for a power up test. If you can't locate the power on pins of the motherboard in the docs you may be way in over your head but as you know, everything is now suspect.
So back to the beginning with the least number of parts.
If you can't find power on pins, take it to the shop that does your repairs.
My pc wont start no matter what i do anymore. The power button does nothing, and i have tried finding the on/off pins but can't seem to do it correctly. When i use the reset button on the back of my psu everything turns on, the fans and stuff. I can't figure out why it wont turn on. (p.s. my sister threw the desktop)

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