Question System powers off randomly ?

Nov 1, 2021
PC shuts down with no warning and I am out of leads

Over the past 6 months I have ran into the issue of my system powering off then back on for seemingly no rhyme or reason. Not a Windows power off either, I mean straight to black screen every component shuts down then immediately back up like its a fresh power on with no errors. Its powered off from loads as simple as Discord being the only app running to gaming, watching YouTube, and talking with friends simultaneously with days to weeks in between occurrence. I have ruled out some of the common issues myself.

  • Cooling is no issue thanks to my 360mm AIO that according to ICUE is working properly.
  • I have a 850w power supply that I rma'd after the first couple of shut offs so hopefully I didn't go two for two on bad units
  • Drivers/Windows/BIOS/Firmware's stay up to date
  • No viruses or malware has been detected
  • No drives have been corrupted
  • My CPU only has no extra overclocking that could cause instability
  • Event logs don’t really point me in any direction. At the time of shut off there’s a “Unexpected Shutdown” severe event
* I changed motherboards from my original MSI MPG Z390M to an allegedly new ASUS ROG Strix Z390-E but both have the issue.
If anyone has the slightest idea that would be greatly appreciated. My job is discussing working from home recently and I would much rather have a fully functional system than have to use the craptop I use in the office. My desktop specs are as follows.

CPU - i9 9900k

RAM - 32GB (16x2) 3200

GPU- EVGA FTW3 Ultra 3080ti

Motherboard - ASUS ROG Strix Z390-E

PSU - EVGA SuperNOVA 850 G5

OS - Windows 10 (21H2)

Storage - SAMSUNG 980 SSD 1TB
just a thought have you got the "asus armoury crate" installed it might show a driver maybe you are on the latest bios version just a few thoughts.
normally on the asus page for your motherboard at the end.
a very usefull tool in itself.
click the cog icon and update centre.