For the past ~2 years maybe my PC would randomly turn off and not reboot until I unplugged the 24pin connector from the mobo for a about 30 secs, it'd only happen once in awhile so I never thought much of it but now it's happening all the time.
It'll shut off out of no where, if I turn off and on the PSU it'll boot on for half a second and shut down again, until I replug the 24pin.
Sometimes instead of turning off my screen will go black followed by a loud buzzing from my speakers and all the fans ramp to 100%, followed by it not turning on again.
I turned off "automatic restart" as suggested somewhere else to no avail.
I ran memtest with no errors, stress tested it with prime95 and 3dmark to see if it causes it but nothing, it seems to be completely random. I'm guessing either the mobo or the PSU but I'm not sure which, I MIGHTVE replaced the PSU since it started happening (needed to when I bought a new GPU) but I don't remember for sure.
Any way to tell which part is causing the problem?