I disabled it on the monitors, which are the same brand albeit differing sizes/models, and also the AMD GPU settings. This seems to have solved the issue. I'll be keeping watch for any additional issues.
Original Post: So I've been having problems with flickering, but I'm not sure to ever call it full on studdering, for a bit now. It comes and goes and is difficult to determine. However , it was to the point where it was driving me mad so I tried to examine what might be causing it.
The short version is that it was not until recently that Windows permitted multiple monitor refresh rates to be used for nearly 13 years, Microsoft seems to have solved a long-forgotten issue with regards to how Windows handles multi-monitor update rates. Windows 10's Desktop Window Manager, (DWM) has caused frame-skips and glitches when several monitors had different refresh rates. Windows 10 2004 20H1's DWM allows GPU scheduling that is hardware-accelerated in WDDM 2.7 is believed to have resolved this issue , as shown by an user on Reddit.
The moment I discovered this issue, I changed my monitors from an 144hz main screen and an alternate 60hz display to both my monitors at 144hz. I made this change because I did not want the process of upgrading my system now as my old 60hz monitor was long due to be upgraded anyway.
However, I did so by upgrading to a larger main screen. This means that my GPU was now running more pixels , at a greater rate of refresh. The GPU was now forced to function, despite being fine for the classic WoW. It wasn't up to the task.
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