Question PC shut down during gameplay and now will not turn on

[Bullszeye]

Hey, I upgraded 2 months ago and I've been using it with small issues (like sometimes having to restart a few times for the pc to actually display anything on my monitor), it being unable to restart (just restarts on a black screen) and taking a long time to boot considering the high end ssd it has. But when it does start it works perfectly and the temperatures are never over 70c on both the gpu and cpu during very heavy loads. I have stress tested this pc and used it heavily for the past 2 months with no issues.

Today, I was streaming some games to my phone over my router (pc is on the other end of the house) and I suddenly lost connection. I walked upstairs to see my PC power buttong being lit but the RGB and fans being off. Unfortunately, I was not in the room at the time so I cannot say what exactly happened when the PC turned off. I tried turning it off and on and nothing happens. The pc components do get power and the MOBO rgb is on (it is on even when the pc is off as long as the PSU switch is on), however the fans don't spin up and the other RGB does not turn on. How do i troubleshoot this? What should I do exactly?

Usually pc boots like this: Power button lights up, 2 second later the AIO pump turns on, then 2 seconds later the RGB fans light up and start spinning then pc boots normally (I know this is all weird but from what I researched it has a lot to do with the z690 being a new platform.)

Upgraded components are (2 month old):
i9 12900k stock (was overclocked for a week but i removed it because i didn't really need the extra speed)
Gigabyte waterforce 360 AIO (3 fans)
Asus rog Z690-e board
2x16gb kingston fury 6000 mhz ram(xmp 1, set to 6000 mhz clock in bios)
Samsung 980 pro 1 tb (boot drive)

Other (components from previous configuration) are:
RTX 3080 ti gigabyte eagle (8 months old)
Samsung 860 evo 500 gig (4 years old)
Kingston 1 tb ssd (2 months old)
Adata 250 gb ssd ( 6 months old)
WD 4 tb hdd (8 years old)
Nzxt c850 gold psu (8 months old)
3 case fans with rgb (coolermaster h500p mesh case)

 

[Ralston18]

Based on your description and hardware specs I suspect that the PSU may be starting to falter and fail.

Even if only 8 months old it could be defective in some manner and not able to keep up with the power demands. Especially if there are sudden peaks in wattage demand.

At the next successful boot look in Reliability History and Event Viewer.

Either one or both may be capturing error codes, warnings, and even informational events related to the shutdowns.

Increasing numbers of errors and varying errors are a sign of a problem PSU.

Remember that PSUs provide three different voltages (3, 5, and 12) to various system components. A problem with any given voltage will cause problems.

Do you have all important data backed up to locations off of the problem PC?

I would be a bit leery of having backups just spread amongst the existing 4 drives..... Especially that eight year old WD 4TB drive.

 

[Bullszeye]

Based on your description and hardware specs I suspect that the PSU may be starting to falter and fail.

Even if only 8 months old it could be defective in some manner and not able to keep up with the power demands. Especially if there are sudden peaks in wattage demand.

At the next successful boot look in Reliability History and Event Viewer.

Either one or both may be capturing error codes, warnings, and even informational events related to the shutdowns.

Increasing numbers of errors and varying errors are a sign of a problem PSU.

Remember that PSUs provide three different voltages (3, 5, and 12) to various system components. A problem with any given voltage will cause problems.

Do you have all important data backed up to locations off of the problem PC?

I would be a bit leery of having backups just spread amongst the existing 4 drives..... Especially that eight year old WD 4TB drive.

The PC now boots normally on integrated graphics if i plug out the power cables out of the GPU. the GPU is not detected though. Could it be a faulty gpu? Im going to try the GPU in a different PC to see if it works there, the PSU would be the best thing to fail right now. I sincerely hope it's not the GPU as it's by far the most expensive to replace.. The pc also now starts somewhat fast and doesn't have boot issues and restart now works. :/ Could it have been the gpu the entire time? Or perhaps the PSU struggling?

 

[Ralston18]

Run Resource Monitor and Task Manager to observe system performance. Use both tools (run as Admin) but use only one tool at a time.

Either one or both may be capturing some error codes, warnings, etc. that you can match to the PC shutdowns and other problems.

Look for entries related to the GPU. Could indeed indicate some problem with the GPU, its' drivers, or some Microsoft process.

Likewise look for increasing numbers of varying errors. That would indicate a faltering PSU.

If possible, swap in another known working PSU. Remember do not mix and match cables from other PSUs.

And PSUs can be tested to some extent. Not a full test because the PSU is not under load.

You need a multi-meter and must know how to use it. Or know someone who does.

FYI:

https://www.lifewire.com/how-to-manually-test-a-power-supply-with-a-multimeter-2626158

Any voltages out of tolerance would make the PSU even more suspect.