Running the latest version of Rocky Linux 9 fully updated and Mate on a Dell Inspiron 7570 laptop with a UHD display, i.e. 3840 x 2160 pixels. I would like to attach two external monitors and initially experimented with a Dell dock model 3100 and the latest version of the DisplayLink and evdi drivers. However, although the Mate display applet shows the correct resolution for the laptop display itself and for the external monitor which is running at 1920 x 1080 pixels, the resolution on the second, external display is more like 640 x 480 pixels. While I initially thought this was due to a bug in the DisplayLink/evdi drivers, I see the same issue when I connect the monitor directly to the HDMI output on the laptop itself, ie. DisplayLink/evdi are presumably not involved although they are installed, nor is the dock of course. I just discovered running xrandr --listmonitors that, while the internal laptop monitor is labeled eDP-1, xrandr identifies the external monitor as using DP-1 although it uses the laptop HDMI-connector. Further, while mate hardware display monitor also identifies it as using DP-1 - possibly based on xrandr output - the monitor itself tells me it is connected using its HDMI1 connector. xrandr does report the correct display resolution, though. Thus, it looks like xrandr/nouveau misreads the configuration feeding it to mate. I just updated the laptop BIOS to the very latest version and saw no difference. I am using an HDMI-HDMI cable with no adapters. I have tried both booting with the external monitor already attached and attaching/reattaching it later. The monitor is an Acer S230HL monitor. I am using the nouveau driver and inxi reports the presence of both Intel UHD Graphics 620 and Nvidia GM108M (GeForce 940MX). The kernel is: Linux 5.14.0-503.15.1.el9_5.x86_64 #1 SMP PREEMPT_DYNAMIC Tue Nov 26 17:24:29 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux Could this be an nouveau bug (I am running X11 and not Wayland)? How should I troubleshoot it? Appreciate ideas!
