Question PC boots up, but won't even POST Bios or beep?

[Doginawok]

I Built my PC just over a year ago, but since a week ago the fan has stopped working and the CPU has shutdown from overheating 2 or 3 times. I ordered a new fan and in the meantime I manually respin the fan to get up back up to speed when it stops. However, as of today, the pc shutdown soon after booting, and will not reboot, even to Bios. My monitor lights up and displays text saying "display port no signal" when I turn the pc on, there are no beeps from the pc itself. From googling this problem, most responses seem to be in the context of building the pc. I am wondering what I can do to solve my issue. If my CPU really is fried, what can I do to confirm it? Could it possibly be the motherboard or PSU?

Relevant specs:
Ryzen 2700X
MSI X470 GAMING ATX AM4 Motherboard
Corsair RM 750 PSU

 

[rgd1101]

how did you know it was overheating?

 

[Doginawok]

In hindsight, I don't. When my PC crashes, the fan stops instantly so I dont actually know that its due to CPU overheat from malfunction, it was just the conclusion I reached since the fan stopped working once. The PC is working now after a CMOS reset, and I actually haven't needed to manually start the fan since then.

I'm not sure what a CMOS reset fixes, so I dont really have any other leads as to what the problem was.

 

[rgd1101]

test with another psu?