[SOLVED] Monitor Stutter / Flicker then rebooting itself

[Naldrek]

Hello!

Mi PC reboots randomly. The only symptom is a weird monitor stuttering only in the main display (conected by HDMI to Ryzen 5700XT) right before the reboot (no BSOD, just plain black and reboot).

It doesn't happen during normal use, just while playing, but it has happened on Witcher 3 as well on windowed LOL. The problem itself can't be captured by recording the screen, but here is a small video that shows the problem, recorded with my phone. That's an even simplier game than LOL (ignore the game, pay attention to the sudden black lines).

I have tested the PSU (750W Gold) by doing FurMark + Prime95 stress test, no problem at all. Temperatures aren't the problem either as component gets no hotter than 85 celsius under such stress test.

The secondary monitor is connected through a converter (VGA -> DisplayPort) to the same GPU, but the problem persist even without the secondary monitor.
All parts are new.

Any ideas on why this is happening?
Thanks.

 

[SteveRX4]

PC specs?

How hot is your CPU and GPU getting?

Are you getting any error messages?

 

[Naldrek]

I solved my problem and decided I could share it here.
The solution was simple: do not use a splitter to power the GPU. I'm talking about cables like this. They usually come with the PSU and a lot of GPUs need one or more connector. I simply plugged one of these, but not the splitted part, and used another one. So I have "2 main cables" (if that make sense) connected to my GPU.

No more errors of any kind.