I have similar problem with hybrid amd+nvidia setup, but only after wake from sleep (reboot works fine) STEPS TO REPRODUCE 1. Use amd+nvidia hybrid setup (using ryzen 5800 + nvidia 3050 ti) X11 displays configuration: ``` Section "Files" ModulePath "/usr/lib/nvidia" ModulePath "/usr/lib32/nvidia" ModulePath "/usr/lib32/nvidia/xorg/modules" ModulePath "/usr/lib32/xorg/modules" ModulePath "/usr/lib64/nvidia/xorg/modules" ModulePath "/usr/lib64/nvidia/xorg" ModulePath "/usr/lib64/xorg/modules" EndSection Section "ServerLayout" Identifier "layout" Screen 0 "integrated" Inactive "nvidia" Option "AllowNVIDIAGPUScreens" EndSection Section "Device" Identifier "integrated" Driver "modesetting" BusID "PCI:6:0:0" Option "TearFree" "true" Option "DRI" "3" Option "VariableRefresh" "on" Option "AsyncFlipSecondaries" "on" EndSection Section "Screen" Identifier "integrated" Device "integrated" Option "AllowExternalGpus" EndSection Section "Device" Identifier "nvidia" Driver "nvidia" BusID "PCI:1:0:0" Option "RegistryDwords" "EnableBrightnessControl=1" Option "AsyncFlipSecondaries" "on" EndSection Section "Screen" Identifier "nvidia" Device "nvidia" EndSection ``` 2. Connect external screen via type c cable with display port alt mode protocol 3. Put laptop into sleep mode 4. Wake the laptop up from sleep 5. Only internal screen is available, the external one sees no signal 6. Switch to tty2 and back (ctrl+alt+f2 -> ctrl+alt+f1) 7. Kernel refreshed the available screens and the external screen is available once again OBSERVED RESULT External display loses signal after sleep-wakeup cycle EXPECTED RESULT External display reconnects automatically POSSIBLE WORKAROUNDS: Ask kernel/x11 to rescan displays when quirky hardware is detected SOFTWARE/OS VERSIONS Linux/KDE Plasma: (available in About System) archlinux packages KDE Plasma Version: First noticed on 5.26.5, still reproduces on 5.27.2 KDE Frameworks Version: 5.103.0 Qt Version: 5.15.8 NVIDIA drivers: 525.89.02 Linux kernel: 6.2.1-zen1-1-zen OTHER INFO: See also https://bugs.kde.org/show_bug.cgi?id=460341#c118 After fixing the mentioned issue the problem still occurs for me This problem only appears when using type-c <-> dp cable. Does not reproduce with HDMI cable Both ports are internally connected to the NVIDIA GPU. The internal screen is connected to the integrated GPU
> 6. Switch to tty2 and back (ctrl+alt+f2 -> ctrl+alt+f1) > 7. Kernel refreshed the available screens and the external screen is available once again This is quite interesting. It's like the opposite of Bug 466187.
Also reproduces win NVIDIA Only (with amd iGPU turned off in bios) on X11 Does not reproduce on Wayland
It's NVIDIA's bug https://download.nvidia.com/XFree86/Linux-x86_64/545.29.06/README/dynamicpowermanagement.html (Known Issues And Workarounds, p.4)
Thanks for following up!