PC shuts down randomly only when playing games

[Neeedles]

Hello,

So my PC shuts down randomly only when playing games, it can do stress tests with no problem. Furmark is no problem, even with other stress tests and cinebench running at the same time. Doesnt even have to be a hard to run game.
It just shuts down completely as if disconected and restarts itself right away.
What i tried so far is replacing the PSU. Replaced Seasonic 850W Platinum with 750W FP Gold. Changed my MB from Aorus Z390 Elite ti Z390 Pro, and also got new pair of RAM sticks. Running no OC on the cpu right now.
All drivers, windows and bios are up to date.

SPECS:
Z390 Aorus Pro
i9 9900KF stock(cooled by Kraken x72 and temps are fine)
RTX 3080 TUF OC
2x8gb Crucial Ballistix 3000mhz cl15
Kingston A2000 500gb system ssd
Samsung 970EVO 1tb 
Crucial 1tb sata ssd
Seagate barracuda 2tb HDD

DxDiag attached

Thanks very much for any tips 
 

DxDiag.txt

[BuzzingBee]

It's because of Seasonic Prime PSU... They don't like GPU with high power draw such as RTX 3080/3090 and RX 6800XT/6900XT. From what I read the noise from GPU leaked into 12V sense PSU wire, triggering false positive and therefore shutting off the PC.

 

You could try to remove/cut 12V sense wire or buy a new PSU. EDIT: Oops, OP already replaced another PSU. 

Edited October 12, 2021 by BuzzingBee

[Neeedles]

But why does it only happen in games? Doesnt happen with stress tests. And even in games that dont load the gpu nowhere near 100%? Happens with or withput gpu oc as well.

[BuzzingBee]

Not too certain, some people reported experiencing restart/shutdown in certain games while it was fine for other games.

 

I also had multiple restarts, once when the game was still loading which gpu usage should be near 0% usage and memory usage was growing.

 

Do you still have shutdowns with your other PSU?

[Neeedles]

1 hour ago, BuzzingBee said:

Not too certain, some people reported experiencing restart/shutdown in certain games while it was fine for other games.

 

I also had multiple restarts, once when the game was still loading which gpu usage should be near 0% usage and memory usage was growing.

 

Do you still have shutdowns with your other PSU?

Yes its just an instant shutdown with even rgb going dark and immediate restart. What ill try is running the gpu undervolted and see if it still happens