PC Restarting For Some Reason

[III Envoy III]

I am desperate at this point. My PC just keeps restarting itself for no reason and it shows no signs of stopping. I've reverted all overclocks to its default settings in my new Motherboard's BIOS, ran Prime95, Heaven, and CPU-Z benchmarks to see what the issue could be. The CPU under prime95 reached 100% use for about 5 min before I stopped the test, moved to Heaven, and then it crashed again. I"m not entirely sure if it's;s a driver issue since my GPU was just updated yesterday, but the drivers for motherboard that I just installed has not had any drivers changed since I put it in yesterday. I'm stressed out of my mind and am in need of grave assistance. Specs for reference: i5 6600k @3.9GHz with 1.136V, MSI GTX 1070 Quicksilver Edition, Asus Z170S Sabertooth motherboard, Corsair CX550M PSU, 8GB DDR4 HyperX Fury Ram @2133MHz. If anyone can help I need it badly, these crashes are awful. The PC is around 6mo old, built in June, has had no issues on the old mobo (Z170A Krait Gaming) I'm leaning on two main culprits, PSU doesn't have enough wattage, or the very small amount of thermal paste (Arctic Silver 5) that I wiped off for the most part on the affected CPU pins. Other than that, I've no idea what's wrong and need help. Thanks!

 

[Paul NZ]

If you can get into windows run event viewer.

If there are any event id: 41 (63) errors under system this can be a sign of a faulty PSU. Thats if you didnt turn it off by holding down the power button

 

[III Envoy III]

There were a few of those errors that occurred right when the system restarted without me doing anything yes, what should I do to save the rest of my parts if the psu is the culprit? I asked my friend to come over tomorrow with his EVGA 750W psu to test as well. Anything more?

 

[TotoLaser76]

Did you ever get this fixed? I've been having the same issue, but I got a new psu and hado no luck fixing it