I had some problems with my relative new (less than a year old) odyssey g5 monitor flickering when I had it on 144hz and reduced it to 120hz and stopped, not more than a week ago I noticed that after the monitor goes to sleep sometimes it goes blank and doesn’t show anything and I needed to restart. Since yesterday, it refuses to connect and it just power cycles every single time if it goes to sleep. I tried all 3 DP ports. On Windows (same machine, just dual boot) I don’t have these problems, Also when I connected the monitor with HDMI instead, same resolution and same refresh rate it works fine. I suspect that the cable (or the port of the monitor) I have to borrow a cable to test if it’s actually the cable, but it doesn’t make sense why it would only happen on Linux. I deleted kscreen folder just in case without any success. Also, I have multi monitor setup, an old 60hz round monitor connected via DP to VGA the Samsung g5 primary 4k 120hz monitor that has the problem, connected directly to DP and a relative new Samsung 1080p 60hz monitor connected with HDMI and a projector DP to HDMI, but that’s irrelevant because I still have the problem when it’s disconnected. Also, I have Wayland with nvidia but xorg wasn’t any different, so maybe it has something to do with the nvidia drivers on Linux. I couldn’t find someone having a similar problem to this, and I am not sure where I should start to pinpoint the problem. For now, I am connected via HDMI and my HDMI monitor is connected where the projector should be on the DP to HDMI converter. Also, I am running latest plasma on arch Linux (endevourOs) fully updated
P.S. Also the problem gets temporary fixed (until the monitor goes back to sleep) if I disable or re-enable any monitor