Forgive me if I’m not posting this in the correct area. I just got my ftw3 ultra 3080 today and installed it. Did the ddu and fresh driver install and everything. 3 separate pcie cables from an evga 850 GA psu. Did port royal and fire strike and getting above average scores and temps are really good. Games like warzone, halo, gears 5, iracing all worked well so far. Load up shadow of the tomb raider to run its benchmark and while adjusting the settings before I even run the benchmark the pc just completely shuts off like someone flipped the power switch. Reboot and try again and does it again. I’m just really concerned about what on earth could be causing this…anyone have ideas?

try ramping up your system/cpu fans. Also turn off ECO mode on your PSU, then try again see if the restarts happen... 

Is this a brand new GA, or one that you've had for awhile?
 
EVGA had an issue with the GA line of PSUs with the higher end 30 series cards and rebooting under load. Contact EVGA and see about getting your GA RMA'd for a fixed version: https://www.evga.com/about/contactus/ 

I bought it off Amazon last September

Bad power supply.

I certainly believe it could be a power supply but it’s strangely just that one game so far. Even higher demanding games like maxed out control and cyberpunk and it’s fine.

I had a similar problem with my 3090 and a Seasonic 850W Titanium - replacing with a DPP12 1500W fixed the issue. If you undervolt your card and the reboots stop, you have your answer.

dervin3
I certainly believe it could be a power supply but it’s strangely just that one game so far. Even higher demanding games like maxed out control and cyberpunk and it’s fine.

It's more of a peak load type situation with that PSU.  But also remove all overclocks from the CPU and only run straight XMP (or even disable XMP) as part of testing.  I assume this is stock clocks FTW3 100% power limit at 380w.  Along with cutting power, you could also try the XOC 450w bios at full 118% power normal clocks, see if it doesn't hit power limit under load what response you get, but will probably shut off too.  Use HWiNFO or GPU-Z to read the power draw at the connectors and pcie slot.

ty_ger07
Bad power supply.

+1

it's your PSU i know with my 3080ftw i had to go to a 1000watt psu due to power spikes 850watt just wasnt' enough with all i have in my rig i needed a larger PSU.   From what others have shown the higher end gpu spike and cause reboots.   I just ran into again with a 6800xt Red Devil tried a 850 watt psu and same issue went to a evga 1000watt and no more reboots.