Hi,
I have Fedora Linux 41 with KDE Plasma, and I encounter a problem: the screen goes green, and then the system restarts. It happens from time to time, but it happens frequently enough to make me frustrated. My graphics card is an AMD Radeon RX 5600 XT. I read that it can be caused when the monitor is connected to an HDMI port, so I bought an HDMI to DisplayPort cable and connected the monitor to the Display port in my graphics part. Now, there is another problem. The monitor goes dark for a second, and it happens very often. Any idea how to solve the problem? Do I need to install other (non-default) drivers?
Check the journalctl logs for system and user for errors from the amdcpu.
There are different grades of HDMI cables. For the latest 4k displays the older HDMI cables do not allow the higher speed signaling.
Change to DisplayPort will not help is that replacement cable is not a high enough speed version.
TIP: The HDMI consortium only allows the HDMI logo to be used on cables that pass its testing. If you do not see a HDMI logo your cable it is likely low quality.
FYI: This is the same as using a HDMI to HDMI cable.
The GPU card detects that you want HDMI and does he signalling conversion on te card. This is exacly the same as what happens when you use an HDMI to HDMI cable.
Thank you for you quick answer. In that case, I can go back to my original HDMI to HDMI cable. There is an HDMI logo on one side and a “Premium High Speed / HEC” note on the reverse side. When using HDMI to HDMI, there is no problem with the monitor going dark for a second, but then there is a problem with the green screen of death.
When this happens you may find informative logs.
Check using sudo journalctl --since=hh:mm and journalctl --use --since=hh:mm where hh:mm is the time just before the green screen happens.
Thanks again. I have just switched back to an HDMI-to-HDMI cable, and I will check the logs when it happens again.
It happened a few days ago again, and I don’t know what I should look for in the journalctl command output file.
Look for amdgpu and kwin as two likely log sources.