High CPU usage on xorg when the external monitor is plugged in

535.54.03 driver.
When an external monitor is connected, the CPU usage of XOrg is not that high (5-10%), but usage of iGPU skyrockets to like 50-60% (intel_gpu_top) and all of it is the XOrg process (only when the external monitor is connected.) CPU temperatures on idle also skyrocket from 41-42 C to 50-53 C, making the keyboard rather hot to the touch while just idling. Watching a video on YouTube with the external monitor makes overall temperature consistently be at least 55 degrees. Without the external monitor it’s like 44.
A bit unrelated to this thread, but the same thing happens in KDE Wayland, except there’s an additional problem of the external monitor not being able to work at full 60 FPS. If you run glxgears and maximize the window on the external monitor, it will report an FPS of around 51 while also visibly stuttering. When the window is on the internal laptop screen, everything is fine.
Hopefully the issue will be resolved soon, as with this I’m rather discouraged from using my external monitor at all.
nvidia-bug-report.log.gz (1.9 MB)