Question PC turns off when high frame rates are reached

[eg9z]

My PC turns off when high frame rates are reached. Has happened in Osu! and CSGO, which are not graphics intensive games. Tried doing GPU stress tests and the PC doesnt turn off even at 100% load, but these dont run at high frame rates because of the nature of stress testing. Frame capping the games appears to stop the problem.
specs:
GPU - GTX 1080
CPU - ryzen 3900x
RAM - 2 x 16GB @ 3200
PSU - 750w EVGA
can provide more details if needed

 

[Dowell71]

check cables first, all the basic thigngs

 

[NightHawkRMX]

Exact model of psu?

 

[NightHawkRMX]

Cpu and gpu temp under load?

Latest bios and chipset drivees?

 

[eg9z]

check cables first, all the basic thigngs

I checked all the cables and reinstalled windows didn't seem to help.

 

[eg9z]

Exact model of psu?

EVGA Supernova NEX 750B

 

[eg9z]

Cpu and gpu temp under load?

Latest bios and chipset drivees?

GPU runs at around 82-83 degrees max
CPU isn't going above 70 as I'm just running it at stock

I have an ASUS Prime B450 Plus, i haven't touched the BIOS it's just whatever version it came with default