Arch Linux

xelkomy

Member

Registered: 2025-06-04

Posts: 3

[SOLVED] - KDE Plasma HDMI screen flickers when starting powerdevil

Hello everyone,

I recently installed Arch with KDE Plasma (Wayland session), and I'm facing an issue with an external HDMI monitor.

When I start powerdevil (either manually or when it auto-starts with the session), the HDMI display enters a loop where it constantly turns on and off every few seconds.

I’ve confirmed this behavior stops if I kill powerdevil.

Here’s the relevant journal log when this happens:
https://0x0.st/8YUg.txt

I’m on a laptop with hybrid graphics:
AMD Renoir iGPU
NVIDIA GTX 1660 Ti Mobile (with proprietary driver nvidia 570.153.02)

nvidia-smi shows the GPU is recognized and working, and I’m using KDE on Wayland. My HDMI port is wired to the NVIDIA GPU (based on past experience and behavior).

Is there a known issue with powerdevil and hybrid/NVIDIA setups on Wayland? Any workarounds or config suggestions would be appreciated!

Thanks!

---------
edit: I just reinstalled the powerdevil and enable it again and also don't forget to try the solution from @V1del

Last edited by xelkomy (2025-06-04 22:24:41)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 24,448

Re: [SOLVED] - KDE Plasma HDMI screen flickers when starting powerdevil

Going to be an interaction with powerdevils ddcutil integration and your screen reacting allergic to that.  try a

systemctl --user edit plasma-powerdevil.service

and add

[Service]
Environment=POWERDEVIL_NO_DDCUTIL=1

below the comment to create a drop in file disabling ddcutil integration.

Depending on how the integrated screen is wired up this "might" disable brightness control for the integrated display, if it does, another option would be to check your monitors OSD on whether you can disable DDC control there.

xelkomy

Member

Registered: 2025-06-04

Posts: 3

Re: [SOLVED] - KDE Plasma HDMI screen flickers when starting powerdevil

Going to be an interaction with powerdevils ddcutil integration and your screen reacting allergic to that.  try a

systemctl --user edit plasma-powerdevil.service

and add

[Service]
Environment=POWERDEVIL_NO_DDCUTIL=1

below the comment to create a drop in file disabling ddcutil integration.

Depending on how the integrated screen is wired up this "might" disable brightness control for the integrated display, if it does, another option would be to check your monitors OSD on whether you can disable DDC control there.

Thank you so much, I think it fixed by just reinstalled the powerdevil and enable it because out of nowhere the powerdevil was disabled.