Resolution issues after full upgrade - Intel Arc B580

Issues & Assistance
1

Long time linux user, but new to Arch and Cachy. Landed with Cachy after getting fed up with Windows and have been enjoying the experience. I did some digging and wasn’t able to find anything related to my issue, so posting here.

I just did a full upgrade (pacman -Syu). Install went smoothly, but after reboot, the selected resolution is 1920x1080 when before upgrade my system was running fine at 3840 x 2160. The only resolutions “higher” than 1920x1080 to which I have access are 2880 x 576 and 2880 x 480. I’ve tried switching from Wayland to X11, but that had no impact.

I don’t have strong troubleshooting skills in Linux, but am getting better at digging myself. Any suggestions welcome.

❯ inxi -G
Graphics:
Device-1: Intel Battlemage G21 [Arc B580] driver: xe v: kernel
Display: wayland server: X.org v: 1.21.1.21 with: Xwayland v: 24.1.9
compositor: kwin_wayland driver: X: loaded: modesetting dri: iris gpu: xe
resolution: 1920x1080~60Hz
API: EGL v: 1.5 drivers: iris,swrast
platforms: gbm,wayland,x11,surfaceless,device
API: OpenGL v: 4.6 compat-v: 4.5 vendor: intel mesa v: 25.3.4-arch1.2
renderer: Mesa Intel Arc B580 Graphics (BMG G21)
API: Vulkan v: 1.4.335 drivers: intel surfaces: N/A
Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
de: kscreen-console,kscreen-doctor wl: wayland-info
x11: xdpyinfo, xprop, xrandr

2

Another issue that is very likely related…I cannot select HDR any more, the option doesn’t exist in the Display Settings menu.

It seems like a driver issue, but I’m not finding any reference to it in the Arch or Cachy forums.

3

I attempted to force the resolution using xrandr with no luck.

4

First off, x11 does not support HDR. Second, are you using HDMI or DP to connect to your display? I think kwin has a bug with HDMI, as another user had similar issues with getting his 4K TV to work right with HDMI when using a KDE wayland session.

In general, always use DP if you have the option. If you are using a TV, then check if the TV has any options in the GUI to change for that port (like use “standard” over “auto” or “compatibility”).

And know that for 4k@60Hz with HDR enabled requires HDMI 2.1 on the GPU and an HDMI 2.1 certified cable (the required data rate is 15.68Gb/s which HDMI 2.0 cannot provide, 14.4Gb/s max).

Can you try another DE like Sway, Cosmic, GNOME, etc. (that does not use kwin) for comparison?

https://discuss.cachyos.org/t/target-refresh-rate-on-big-screen-not-available-under-wayland

5

Thanks for the thoughtful response. I have the correct hdmi 2.1 cable, a video card that supports 4k and will look in to the bug. I hadn’t had any problem until the last cachy update.

I’ll give another de a try and report back.

6

Do you have an update on this?