Question Overheating and shutting down, now games stutter after replacing cooler?

[Midinette]

Here's the series of events as they happened. About 2 and a half years ago I bought a prebuilt pc from ibuypower (See images with 2060 gpu). About a month ago it started overheating (90c+ while troubleshooting drivers) and shutting down and it was determined that it must be the stock 120mm aio liquid cooler it came with failing so it was replaced with a new Hyper 212 Halo Black air cooler. Now temps are completely fine.

HOWEVER since replacing the cooler I had two new persistent issues. One was a weird screen flicker with black shapes (see images) appearing when watching videos on Facebook Youtube etc. The other issue was World of Warcraft going from smooth to immediately [vulgar language removed] stuttering when pulling a boss and coming under load. It continues for a little while but does level off for the most part and gameplay becomes much smoother albeit still laggy. I never had any issues at all with lagging or stuttering before this.

I dug out my old Radeon XFX RX 480 (see images) and tried using that instead of the RTX 2060 and thankfully the screen flickers have stopped. Could the cpu overheating damage the gpu somehow?

The stuttering in WoW however did not stop after trying a different gpu. What could be causing this to happen? The system overall seems like it's a little slower than it should be when launching programs so could the cpu have been damaged?

 

[Lutfij]

Did you run DDU while on your older GPU, to rule out a corruption with your drivers? Run DDU to remove all GPU drivers, then manually reinstall the latest GPU driver(source from manufacturer's site) in an elevated command.

Your screenshots won't include the make and model of the PSU, this is where you manually mention it. Do the same for your case and your ambient room air temps. How old is the PSU?

 

[Midinette]

Did you run DDU while on your older GPU, to rule out a corruption with your drivers? Run DDU to remove all GPU drivers, then manually reinstall the latest GPU driver(source from manufacturer's site) in an elevated command.

Your screenshots won't include the make and model of the PSU, this is where you manually mention it. Do the same for your case and your ambient room air temps. How old is the PSU?

Sorry what is an elevated command? I'm not super savvy with these things. PSU is 600 watt 80 plus gold. The case is slate hako mr mid tower case. The PSU is what came with the pc when I bought it. Ambient room temps are about 76F but there aren't any issues with cooling anymore. Even during the stutters there's no spike in temps.