SUMMARY On my KDE Neon 20.04 Testing Edition with 5.8.0-31 kernel & dual 1080p+2160p setup, the display scaled down to 1024x768 and only showed it on my 4K monitor (can't change the resolution from Plasma's display settings). I tried opening NVIDIA settings and nothing showed up, either. Reverting back to 450 fixed it. STEPS TO REPRODUCE 1. Install NVIDIA 455 2. Reboot OBSERVED RESULT The output only shows up on the 4K monitor, but not on the 1080p monitor. Upon login, nothing shows up for NVIDIA settings. and output is 1024x768 on the 4K monitor. Also unable to change the resolution. EXPECTED RESULT Should work normally, with 4K+1080p, and desktop layout not changing. SOFTWARE/OS VERSIONS Operating System: KDE neon Testing Edition KDE Plasma Version: 5.20.4 KDE Frameworks Version: 5.77.0 Qt Version: 5.15.2 Kernel Version: 5.8.0-31-generic OS Type: 64-bit Processors: 4 × Intel® Core™ i5-6500 CPU @ 3.20GHz Memory: 15.6 GiB of RAM Graphics Processor: GeForce GTX 1060 6GB/PCIe/SSE2 ADDITIONAL INFORMATION I'm on KDE Neon Testing Edition.
If reverting the driver fixes it, this is most likely an issue in the NVIDIA driver itself. Please report it to the NVIDIA folks. Thank1
What Nate said. You can either send an email to linux-bugs@nvidia.com or make a post here https://forums.developer.nvidia.com/c/gpu-unix-graphics/linux/ It would be helpful if you could run nvidia-bug-report.sh and attach the resulting file in your report.
Created attachment 133985 [details] NVIDIA bug report Here's the output from the NVIDIA.
*** Bug 430379 has been marked as a duplicate of this bug. ***
I posted it on NVIDIA developer forum https://forums.developer.nvidia.com/t/nvidia-455-not-working-properly-on-plasma-5-20-kde-neon-20-04/164150