My laptop screen is 3840x2160@60Hz and my external monitor is 5120x2160@50Hz.
It works smoothly like only using laptop screen without connecting external monitor if I choose
Extend to the right display.
After changing to
Only External monitor display and close laptop screen(it becomes black) in display setting, it’s very sluggish that I need to wait for typing. Changing resolution of external monitor to 3440x1440@72Hz in display settings doesn’t help. It seems like Qubes OS is still consuming resource for closed laptop screen. Is there anyway to detect this?
I have already increased RAM in dom0
qvm-features dom0 gui-videoram-min 166400