So I got this brand new PC assembled at the local shop. See specs below. Every time I try to play something, 5 to 20 min into the gameplay the screen freezes for a few seconds and then PC reboots. Any game I try, any resolution. Just games.  Otherwise everything works flawlessly. I took it back to the shop and they ran every stress test they could come up with and couldn't find any issues. Their last best idea was for me to post on this forum, since these cards seem to be developing reputation for being defective.  All drivers updated. Windows updated. BIOS updated. Debug mode not helping. Unfortunately the whole world seems to be out of stock on any kind of decent video card, so I can't swap it to narrow down the problem. Any way to narrow down and isolate the issue ? Are there any logs anywhere I can see that would help ?    This situation is beyond frustrating. 
 
CPU Intel Core i9 10850k
Mortherboard. ASUS B460M-A
GPU: EVGA Geforce 3080 FTW3
RAM:  Crucial Technologies 32 G (2x16)
PSU : Corsair RM 850
 

I wonder if they Daisy chained any the 3 PICE connections on the card, I have a 750w PSU and currently can't run MSFS 2020 and I think its a spike the PSU cant hold, I Ordered a RM850X to hopefully resolve this issue, I would ask what they are using to stress test it? and I would Run your own stress tests