Hi there,
I have a pressing issue with external displays that aren’t recognized any more. This hit me quite hard when I had to present at a conference and the beamer just wouldn’t connect.
My setup (brief version, full inxi output at the end):
- Tuxedo Sirius 16 Gen2
- has a AMD iGPU and AMD dGPU
- has HDMI Port wich I use to connect my monitor(s), but the issue also appears when using a USB dock and plugging a monitor there.
- CachyOS with Plasma 6, always latest version
When I tried turning it off and on again™, with the external display already plugged in to the HDMI port, it worked. Only when plugging/unplugging to the already running system it won’t work.
This wasn’t always the case; It must have been introduced likely around mid-October 2025, because I didn’t make any updates between mid-October and mid-November, when the issue hit me.
What I’ve tried so far:
sudo udevadm monitor --udev
-
Shows events when the external monitor already is connected during startup
-
Shows no event at all when plugging / unplugging after the system was started.
killall kwin_wayland & kwin_wayland &
Allows me to “kick off” the monitor detection when I plugged the monitor in after the system was started.
Of course, manually working around the issue is not a permanent solution. Neither would be to work around it with a systemd service that restarts kwin_wayland a few s after startup.
Do you have any ideas where the issue could come from?
Here are the relevant parts of inxi -Fxxxz as of now:
System:
Kernel: 6.19.8-1-cachyos arch: x86_64 bits: 64 compiler: clang v: 21.1.8
clocksource: tsc
Desktop: KDE Plasma v: 6.6.2 tk: Qt v: N/A wm: kwin_wayland dm: N/A
Distro: CachyOS base: Arch Linux
Machine:
Type: Laptop System: TUXEDO product: TUXEDO Sirius 16 Gen2 v: N/A
serial: <filter> Chassis: type: 10 serial: N/A
Mobo: NB04 model: AHP958 serial: <filter> part-nu: SIRIUS1602
uuid: c7d36300-dd47-11ee-a062-54cb8298c127 Firmware: UEFI vendor: American
Megatrends LLC. v: AHP958_V1.01A01 date: 12/04/2024
Battery:
ID-1: BAT0 charge: 80.1 Wh (100%) condition: 80.1/80.1 Wh (100%)
volts: 17.42 min: N/A model: AMD Battery Li-ion Real Battery type: Li-ion
serial: <filter> charging: status: not charging cycles: N/A
CPU:
Info: 8-core model: AMD Ryzen 7 8845HS w/ Radeon 780M Graphics bits: 64
type: MT MCP smt: enabled arch: Zen 4 rev: 2 cache: L1: 512 KiB L2: 8 MiB
L3: 16 MiB
Speed (MHz): avg: 3752 min/max: 419/5138 boost: enabled volts: 1.2 V
ext-clock: 100 MHz cores: 1: 3752 2: 3752 3: 3752 4: 3752 5: 3752 6: 3752
7: 3752 8: 3752 9: 3752 10: 3752 11: 3752 12: 3752 13: 3752 14: 3752
15: 3752 16: 3752 bogomips: 121367
Flags-basic: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 sse4a
ssse3 svm
Graphics:
Device-1: Advanced Micro Devices [AMD/ATI] Navi 33 [Radeon RX 7600/7600
XT/7600M XT/7600S/7700S / PRO W7600] vendor: Emdoor Digital driver: amdgpu
v: kernel arch: RDNA-3 pcie: speed: 16 GT/s lanes: 8 ports:
active: HDMI-A-1 empty: DP-1,Writeback-1,eDP-1 bus-ID: 03:00.0
chip-ID: 1002:7480 class-ID: 0300
Device-2: Advanced Micro Devices [AMD/ATI] HawkPoint1
vendor: Emdoor Digital driver: amdgpu v: kernel arch: RDNA-3 pcie:
speed: 16 GT/s lanes: 16 ports: active: eDP-2 empty: DP-2, DP-3, DP-4,
DP-5, DP-6, DP-7, DP-8, DP-9, Writeback-2 bus-ID: 68:00.0
chip-ID: 1002:1900 class-ID: 0300 temp: 33.0 C
Device-3: AVerMedia Live Streamer CAM 313 driver: snd-usb-audio,uvcvideo
type: USB rev: 2.0 speed: 480 Mb/s lanes: 1 bus-ID: 1-1.2.4:11
chip-ID: 07ca:313a class-ID: 0102 serial: <filter>
Device-4: Microdia Integrated Camera driver: uvcvideo type: USB rev: 2.0
speed: 480 Mb/s lanes: 1 bus-ID: 3-1:2 chip-ID: 0c45:6362 class-ID: 0e02
serial: <filter>
Display: unspecified server: X.Org v: 24.1.9 with: Xwayland v: 24.1.9
compositor: kwin_wayland driver: gpu: amdgpu display-ID: :0 screens: 1
Screen-1: 0 s-res: 5440x1889 s-dpi: 96 s-size: 1439x499mm (56.65x19.65")
s-diag: 1523mm (59.96")
Monitor-1: not-matched mapped: HDMI-A-1 pos: top-left res: mode: 2880x1620
hz: 60 scale: 100% (1) dpi: 143 size: 510x290mm (20.08x11.42")
diag: 587mm (23.1") modes: N/A
Monitor-2: not-matched mapped: eDP-2 pos: primary,bottom-r res:
mode: 2560x1440 hz: 240 scale: 100% (1) dpi: 183
size: 355x200mm (13.98x7.87") diag: 407mm (16.04") modes: N/A
API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
device: 1 drv: radeonsi device: 2 drv: swrast gbm: drv: radeonsi
surfaceless: drv: radeonsi x11: drv: radeonsi inactive: wayland
API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 26.0.2-arch2.3
glx-v: 1.4 direct-render: yes renderer: AMD Radeon 780M Graphics (radeonsi
phoenix ACO DRM 3.64 6.19.8-1-cachyos) device-ID: 1002:1900
API: Vulkan v: 1.4.341 layers: 2 surfaces: N/A device: 0
type: integrated-gpu hw: amd driver: mesa radv device-ID: 1002:1900
device: 1 type: discrete-gpu hw: amd driver: mesa radv
device-ID: 1002:7480
Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
de: kscreen-console,kscreen-doctor gpu: amdgpu_top wl: wayland-info
x11: xdpyinfo, xprop, xrandr
Audio:
Device-1: Advanced Micro Devices [AMD/ATI] Navi 31 HDMI/DP Audio
driver: snd_hda_intel v: kernel pcie: speed: 16 GT/s lanes: 8
bus-ID: 03:00.1 chip-ID: 1002:ab30 class-ID: 0403
Device-2: Advanced Micro Devices [AMD/ATI] Radeon High Definition Audio
driver: snd_hda_intel v: kernel pcie: speed: 16 GT/s lanes: 16
bus-ID: 68:00.1 chip-ID: 1002:1640 class-ID: 0403
Device-3: Advanced Micro Devices [AMD] Audio Coprocessor
vendor: Emdoor Digital driver: snd_pci_ps v: kernel pcie: speed: 16 GT/s
lanes: 16 bus-ID: 68:00.5 chip-ID: 1022:15e2 class-ID: 0480
Device-4: Advanced Micro Devices [AMD] Ryzen HD Audio
vendor: Emdoor Digital driver: snd_hda_intel v: kernel pcie: speed: 16 GT/s
lanes: 16 bus-ID: 68:00.6 chip-ID: 1022:15e3 class-ID: 0403
Device-5: AVerMedia Live Streamer CAM 313 driver: snd-usb-audio,uvcvideo
type: USB rev: 2.0 speed: 480 Mb/s lanes: 1 bus-ID: 1-1.2.4:11
chip-ID: 07ca:313a class-ID: 0102 serial: <filter>
API: ALSA v: k6.19.8-1-cachyos status: kernel-api
Server-1: sndiod v: N/A status: off
Server-2: JACK v: 1.9.22 status: off
Server-3: PipeWire v: 1.6.1 status: n/a (root, process) with:
1: pipewire-pulse status: active 2: wireplumber status: active
3: pipewire-alsa type: plugin
Info:
Memory: total: 32 GiB note: est. available: 30.64 GiB used: 7.45 GiB (24.3%)
Processes: 460 Power: uptime: 48m states: freeze,mem,disk suspend: s2idle
wakeups: 0 hibernate: platform Init: systemd v: 259 default: graphical
Packages: 1889 pm: pacman pkgs: 1883 pm: flatpak pkgs: 6 Compilers:
clang: 22.1.1 gcc: 15.2.1 Shell: Sudo (sudo) v: 1.9.17p2 default: Bash
v: 5.3.9 running-in: konsole inxi: 3.3.40
Cheers,
Uwe