Created attachment 175350 [details] kscreen-doctor -o | ansifilter > kscreen.txt SUMMARY kscreen-doctor reports RgbRange "unknown" and a peak brightness of 0 nits for the LG CX STEPS TO REPRODUCE 1. navigate to the terminal and run kscreen-doctor -o OBSERVED RESULT see attachment EXPECTED RESULT RGB range should not be unknown and peak brightness should be greater than 0 nits SOFTWARE/OS VERSIONS Linux/KDE Plasma: Operating System: Fedora Linux 41 KDE Plasma Version: 6.2.2 KDE Frameworks Version: 6.7.0 Qt Version: 6.7.2 Kernel Version: 6.11.5-300.fc41.x86_64 (64-bit) Graphics Platform: Wayland Processors: 16 × AMD Ryzen 7 7800X3D 8-Core Processor Memory: 30.5 GiB of RAM Graphics Processor: NVIDIA GeForce RTX 4090/PCIe/SSE2 ADDITIONAL INFORMATION Output: 1 HDMI-A-2: refers to the LG CX Output: 2 DP-3: refers to a Denon x3800H which is plugged in via DP -> HDMI adapter The ladder is not plugged into any other device via HDMI passthrough. Both devices are connected to the same Nvidia 4090 GPU via HDMI + DP ports modinfo -F version nvidia 565.57.01 Note: It's unlikely that this is issue is exclusive to the 565 beta drivers I've actually never seen it work properly even with previous stable releases.
This is expected. Your graphics driver doesn't support reporting or controlling rgb range, and the screen doesn't report a peak brightness (which is what the zero means).
A possibly relevant merge request was started @ https://invent.kde.org/plasma/libkscreen/-/merge_requests/205
Git commit 5e019ba5dba8da4509849b6f821a24a145421b89 by Xaver Hugl. Committed on 06/11/2024 at 12:34. Pushed by zamundaaa into branch 'master'. doctor: clarify the meaning of max. brightness zero M +10 -2 src/doctor/doctor.cpp https://invent.kde.org/plasma/libkscreen/-/commit/5e019ba5dba8da4509849b6f821a24a145421b89
Git commit 7660ca1b6ccd2beeaaf40f91f8fd64ec3e6bb704 by Xaver Hugl. Committed on 07/11/2024 at 13:45. Pushed by zamundaaa into branch 'Plasma/6.2'. doctor: clarify the meaning of max. brightness zero (cherry picked from commit 5e019ba5dba8da4509849b6f821a24a145421b89) Co-authored-by: Xaver Hugl <xaver.hugl@gmail.com> M +10 -2 src/doctor/doctor.cpp https://invent.kde.org/plasma/libkscreen/-/commit/7660ca1b6ccd2beeaaf40f91f8fd64ec3e6bb704