SUMMARY I have a LG 50UK6500AUA TV (https://www.lg.com/us/tvs/lg-50UK6500AUA-4k-uhd-tv) connected to my computer. The default resolution and refresh rate is 1080p60, but it supports up to 4K60. 4K is available, but only at up to 30 Hz. There are also several dimension/refresh rate combos that are not at all supported by the TV. STEPS TO REPRODUCE 1. Connect to LG 50UK6500AUA via HDMI. 2. Open System Settings and go to the Display settings. OBSERVED RESULT The default is 1080p60 and the highest resolution is 4K30. EXPECTED RESULT The default is 4K60 and only supported resolutions are shown. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Fedora Linux 43 KDE Plasma Version: 6.5.2 KDE Frameworks Version: 6.19.0 Qt Version: 6.10.0 ADDITIONAL INFORMATION This behavior is consistent across both Fedora 43 and KDE Linux on both a NVIDIA desktop computer and a Raspberry Pi 4. This issue is not present on the X11 session.
The driver decides which modes are supported, please report the 4k60 mode being missing at https://forums.developer.nvidia.com/c/gpu-graphics/linux for NVidia, I don't know where bugs on the Pi should be reported to. The added modes the display doesn't natively support are a feature, see bug 448398
Thank you!