Need help for Monitor-Configuration


i am using a LG Ultrawide capable to display a resulotion of 2560x1080 pixel.
I have found some configuration-examples in different forums but they are not working well for my display. Looks ugly.

The monitor is added with a display-potz to hdmi adapter to an old Toshiba laptop.

Maybe someone can help me.

I made following configuration:

xrandr --newmode “2560_1080_60.00” 185.58 2560 2624 2688 2784 1080 1083 1093 1111 -HSync -Vsync
xrandr --addmode DisplayPort-0 2560_1080_60.00
xrandr --output DisplayPort-0 --mode 2560_1080_60.00

But the result is illisble.

The monitor-specs i got :

23: None 01.0: 10002 LCD Monitor
[Created at monitor.125]
Unique ID: wkFv.T8Ll_1adMKA
Parent ID: VCu0.QctWuGieLU1
Hardware Class: monitor
Device: eisa 0x59f1 “LG ULTRAWIDE”
Serial ID: “455344”
Resolution: 720x400@70Hz
Resolution: 640x480@60Hz
Resolution: 640x480@75Hz
Resolution: 800x600@60Hz
Resolution: 800x600@75Hz
Resolution: 1024x768@60Hz
Resolution: 1024x768@75Hz
Resolution: 1280x1024@75Hz
Resolution: 1152x864@75Hz
Resolution: 1280x1024@60Hz
Resolution: 1280x720@60Hz
Resolution: 1600x900@60Hz
Resolution: 1920x1080@60Hz
Resolution: 2560x1080@60Hz
Size: 673x284 mm
Year of Manufacture: 2019
Week of Manufacture: 9
Detailed Timings #0:
Resolution: 2560x1080
Horizontal: 2560 2624 2688 2784 (+64 +128 +224) -hsync
Vertical: 1080 1083 1093 1111 (+3 +13 +31) -vsync
Frequencies: 185.58 MHz, 66.66 kHz, 60.00 Hz
Year of Manufacture: 2019
Week of Manufacture: 9
Detailed Timings #1:
Resolution: 1920x1080
Horizontal: 1920 2008 2052 2200 (+88 +132 +280) +hsync
Vertical: 1080 1084 1089 1125 (+4 +9 +45) +vsync
Frequencies: 148.50 MHz, 67.50 kHz, 60.00 Hz
Driver Info #0:
Max. Resolution: 2560x1080
Vert. Sync Range: 56-75 Hz
Hor. Sync Range: 30-90 kHz
Bandwidth: 185 MHz
Config Status: cfg=new, avail=yes, need=no, active=unknown
Attached to: #8 (VGA compatible controller)

[FONT=arial]Thanks much for help ans kind regards



Why do you need to add a mode? Couldn’t you just choose one of the monitors reported modes when xrand is run with no parameters? For example:

% xrandr
DP-4 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
   3840x2160     60.00*+  30.00   
   2560x1440     59.95   
   1920x1080     60.00    59.94   
   1600x900      60.00   
   1280x1024     60.02   
   1280x800      59.81   
   1280x720      60.00    59.94   
   1152x864      59.96   
   1024x768      60.00   
   800x600       60.32   
   720x480       59.94   
   640x480       59.94    59.93

% xrandr --output DP-4 --mode 3840x2160
# Or even...
% xrandr --output DP-4 --mode auto

The above is mostly based on what I’ve read at

I thought setting modes wasn’t really necessary any more.

This is all the data Xorg needs to auto-generate proper modelines in cases when the EDID is not producing proper results, though it does need to be properly reformatted for placement in /etc/X11/xorg.con*. Manual modeline generators cannot do any better.

When was the laptop made? Please provide output from running inxi -SGayz and cat /var/log/Xorg.0.log | susepaste with the external LG display connected but without using xrandr or /etc/X11/xorg.con* or your DE to try to configure it.

Which end of the adapter connects to display end, and which to laptop end? AFAIK, most DP to HDMI adapters only convert DP to HDMI, not HDMI to DP. Doesn’t the LG have both DP and HDMI inputs, so that you could use a cable that’s the same on both ends?

I think the OP should be using hdmi on the old toshiba laptop as that’s the output, I think they are connecting the display port on the monitor…

Kernel: 5.17.3-1-default x86_64 bits: 64 compiler: gcc v: 11.2.1
parameters: BOOT_IMAGE=/boot/vmlinuz-5.17.3-1-default
root=UUID=47b309aa-721b-4a6a-a045-a5084bae700f splash=silent
mitigations=auto quiet security=apparmor
Desktop: KDE Plasma 5.24.4 tk: Qt 5.15.2 wm: kwin_x11 vt: 7 dm: SDDM
Distro: openSUSE Tumbleweed 20220419
Device-1: AMD Thames [Radeon HD 7550M/7570M/7650M] vendor: Hewlett-Packard
driver: radeon v: kernel alternate: amdgpu bus-ID: 01:00.0
chip-ID: 1002:6841 class-ID: 0300
Device-2: Chicony Integrated HP HD Webcam type: USB driver: uvcvideo
bus-ID: 3-1.3:4 chip-ID: 04f2:b230 class-ID: 0e02 serial: <filter>
Display: x11 server: X.Org 21.1.3 compositor: kwin_x11 driver:
loaded: ati,radeon unloaded: fbdev,modesetting,vesa display-ID: :0
screens: 1
Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 507x285mm (20.0x11.2")
s-diag: 582mm (22.9")
Monitor-1: DisplayPort-0 res: 1920x1080 hz: 60 dpi: 72
size: 673x284mm (26.5x11.2") diag: 730mm (28.8")
OpenGL: renderer: AMD TURKS (DRM 2.50.0 / 5.17.3-1-default LLVM 14.0.0)
v: 3.3 Mesa 22.0.1 compat-v: 3.1 direct render: Yes

And here is teh link :

[FONT=monospace]Pasted as:
Link is also in your clipboard.

I have only a display-port out on the laptop-side and a hdmi in on the monitor. so i am unable to change anything.


I have made a configuration manually. But it is not usable because of jittering and glittering :slight_smile:

So i think that my settings are incorrect. i got them from another posting regarding the lg ultrawide. But i think the displays are not 100% equal in their specs…

Output from inxi and Xorg.0.log seem to have inconsistencies. Please run sudo inxi -U to upgrade inxi, then provide I/O from inxi -SGIayz again, along with xrandr --listproviders, and xrandr I/O.

Please paste them here.