[SOLVED] Setting the correct resolution of a screen connected via HDMI

eklatea · 2022-04-30 14:17:26

Original title: Setting the correct resolution of a screen connected via HDMI adapter

Hi. I recently built a new PC with a AMD graphics card and am using the open source drivers. However my card only has one HDMI output so I use a Displayport to HDMI adapter to connect my second screen.

Desktop environment is KDE Plasma with x11. The second screen is in fact connected, however the maximum resolution I can select / the only one is 640 x 480 and the screen is a 1920x1080 60hz display that works fine via HDMI.

I tried using xrandr as described to add a custom resolution and added it to the display, however when I try to change the mode manually via xrandr I get the following error message:

xrandr --output XWAYLAND3 --mode 1920x1080_60.00
X Error of failed request: BadValue (integer parameter out of range for operation)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 21 (RRSetCrtcConfig)
Value in failed request: 0x780
Serial number of failed request: 29
Current serial number in output stream: 29

XWAYLAND3 being the display. Also it's called wayland even though I selected x11 while logging in in KDE. However this might be my own confusion since I'm new.

This is my xrandr output now:

Screen 0: minimum 16 x 16, current 2560 x 1080, maximum 32767 x 32767
XWAYLAND1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 520mm x 290mm
1920x1080 59.96*+
1440x1080 59.99
1400x1050 59.98
1280x1024 59.89
1280x960 59.94
1152x864 59.96
1024x768 59.92
800x600 59.86
640x480 59.38
320x240 59.52
1680x1050 59.95
1440x900 59.89
1280x800 59.81
720x480 59.71
640x400 59.95
320x200 58.96
1600x900 59.95
1368x768 59.88
1280x720 59.86
1024x576 59.90
864x486 59.92
720x400 59.55
640x350 59.77
XWAYLAND3 connected 640x480+1920+0 (normal left inverted right x axis y axis) 0mm x 0mm
640x480 59.38*+
320x240 59.52
640x400 59.20
320x200 58.96
640x350 59.77
1920x1080_60.00 59.96

XWAYLAND1 is my other monitor connected via the actual HDMI port. That one's running just fine.

Hopefully I did this correctly. All the posts I found so far aren't any help at all or lead nowwhere but maybe one of you could offer some advice. Thank you very much in advance.

Solution: Turns out, plasma started wayland instead of the selected x11 session. Only x11 recognizes the screen connected via adapter, wayland doesn't do that properly.

Last edited by eklatea (2022-04-30 15:24:49)

seth · 2022-04-30 15:14:11

Desktop environment is KDE Plasma with x11.

XWAYLAND1 is my other monitor connected via the actual HDMI port.

Also it's called wayland even though I selected x11 while logging in in KDE.

Think about that… then check "loginctl session-status"

eklatea · 2022-04-30 15:21:46

Can't believe I've done this. Sorry, beginner mistake!

When I first connected it, the (connected via HDMI) screen behaved weirdly, and despite checking x11 as session (I double checked that!) it started wayland which I never set up or used. I am not sure why.

It works on xorg ... not sure why wayland doesn't want to recognize the screen through the adapter but it works with x11.

seth · 2022-04-30 15:27:38

It'll fail to obtain an EDID, you could try to provide one: https://wiki.archlinux.org/title/Kernel … s_and_EDID

Arch Linux

#1 2022-04-30 14:17:26

[SOLVED] Setting the correct resolution of a screen connected via HDMI

#2 2022-04-30 15:14:11

Re: [SOLVED] Setting the correct resolution of a screen connected via HDMI

#3 2022-04-30 15:21:46

Re: [SOLVED] Setting the correct resolution of a screen connected via HDMI

#4 2022-04-30 15:27:38

Re: [SOLVED] Setting the correct resolution of a screen connected via HDMI

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