Leap 16.0 - monitor configuration keeps changing

English Hardware
21

Don’t really know, don’t use X11 any more, no issues with three different system with the 630 GPU, all good at 1080P DP → HDMI. I did have a Dell P2018H running on them as well, no issues.

22

I did some experimenting here with 16.0 on my Intel Rocket Lake with 3 displays, and believe the following should work for OP on X11, and could possibly work on Wayland as well, as file /etc/X11/xorg.conf:

Section "Device"
    Identifier "OnlyDevice"
#	Driver	"modesetting"
	Option	"monitor-DP-1"	"D-DP1"
	Option	"monitor-DP-2"	"D-DP2"
EndSection

Section "Monitor"
    Identifier      "D-DP1"
#	VendorName	"Idek"
#	ModelName	"PL4380UH"
#	HorizSync       30-330
#	VertRefresh     30-144
	Option		"Primary"
#	Option          "PreferredMode" "3840x2160"
EndSection

Section "Monitor"
    Identifier      "D-DP2"
#	VendorName	"Dell"
#	ModelName	"U2412M"
#	HorizSync	30-83
#	VertRefresh	50-61
#	Option          "PreferredMode" "1920x1200"
	Option	"Rotate"	"Left"
	Option	"RightOf"	"D-DP"
EndSection

Section "Screen"
    Identifier	"ScreenLeft"
        Device	"OnlyDevice"
        Monitor	"D-DP1"
EndSection

Section "Screen"
    Identifier	"ScreenRight"
	Device		"OnlyDevice"
	Monitor		"D-DP2"
EndSection

The lines commented should be OK whether or not commented, IOW, OK to omit entirely, or uncomment.

23

No Wayland doesn’t use /etc/X11/xorg.conf at all.

1 Like
24

Thank you for the replies, but as I use Wayland it looks as though I’m stumped!

25

We already established DP-2 monitor has no usable EDID at all when connected to a Dell monitor only supporting DP-1.1.

Is switching to an HDMI cable a viable option for you? Or DP to HDMI adapter at the monitor end? This might help with the driver getting EDID read successfully. It will be read over a simple I²C (DDC) channel. Worth a shot if you have such a cable at hand.

Another possible option is to use xrandr to create and set an explicit display mode upon login.

Here’s an example to add a new display mode (monitor must be capable of supporting this mode)…

xrandr --newmode "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
xrandr --addmode DP-2 "1920x1080_60.00"
xrandr --output DP-2 --mode "1920x1080_60.00"

If this works, it can be made persistent by adding it as an autostart script.

26

Thanks for the ideas. I have ordered a cable and if that doesn’t work I will try the second idea.

I will report back in due course…

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27

The monitor has no HDMI input, but it does have DVI. I have been using a DP<>DVI cable for a few days and so far it has been behaving itself.

1 Like