If your monitors going black I'd say we're looking at a GPU issue. Try disconnecting and reconnecting the cable going to the monitor from both the gpu and the monitor. If the problem still persists, try plugging the monitor cable into a different port on your GPU and/or monitor. If the problem still persists after that then try a completely different cable, as well as connecting your main monitor to the port the second monitor was connected to. (Basically shuffle cables around a ton) If none of this fixes your problem. Try running furmark and see if your PC crashes. (Do the same with Prime 95 as I said before.)
Ok this part is EXTREMELY IMPORTANT
You are using a 650watt PSU
Your GPU has a TBP (Total Board Power) of 225W
Your CPU pulls up to 235W
(650-225)-235=190W
With that amount of wattage left over you
should be fine, but you could very well not be. Disable any and all OCs you have (I assume you already did) and then follow these steps. (Written vaguely as I use AMD and am not 100% sure how to do it on NVIDIA)
Go into Nvidia Control Panel
Find the Power Settings
Lower the maximum power draw for your GPU by like 50%.
Run furmark to make sure your GPU won't outright crash due to changing this setting. (If it crashes do googling for how to reduce power draw 2080 and follow its instructions just to the extreme (you might have to decrease clocks too to make it run stable))
Use the PC like you normally would.
If your PC does not crash there are two possibilities.
- Your GPU is failing and cannot handle stock settings.
- Your PSU can't support your PC and you need a chonkier one.
I know this may sound ridiculous but let me share a story with you. (Feel free to skip this part if you aren't doubting my suggestion)
I built my first PC a year or two ago. I was really excited and ready to play some games. One minor problem tho. Whenever I tried to I'd get a kernel power system failure. I rmaed and/or replaced
every single part of my PC minus the case until I eventually bought a 1200W PSU. After that my PC ran good as new. I guess its possible I've got a short somewhere or something like that, I dunno, but since my PC's been running fine for fairly close to a year now, I doubt that's the case.