Ubuntu 20.04 cannot reach resolution 21:9 with an ultrawide monitor

Question

I've just bought an LG 25UM58 ultrawide monitor and set it to work with Windows (dual booting with Ubuntu 20.04). However, in Ubuntu, as I tried to add mode using the following process:

$ cvt 2560 1080 50
# 2560x1080 49.95 Hz (CVT) hsync: 55.65 kHz; pclk: 188.75 MHz
Modeline "2560x1080_50.00"  188.75  2560 2712 2976 3392  1080 1083 1093 1114 -hsync +vsync
$ xrandr --newmode "2560x1080_50.00"  188.75  2560 2712 2976 3392  1080 1083 1093 1114 -hsync +vsync
$ xrandr --addmode DP-0 2560x1080_50.00
X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  140 (RANDR)
  Minor opcode of failed request:  18 (RRAddOutputMode)
  Serial number of failed request:  37
  Current serial number in output stream:  38

My GPU is Nvidia Quadro K420 with 1 DP (ultrawide monitor) and 1 DVI (normal monitor). I have tried different ways (even using the noveau driver which leads to messed up resolution for DVI screen and DP screen became undetected) but the error persists.

UPDATED: Per codlord's suggestion, this is the result when I ran lshw -c video:

  *-display                 
       description: VGA compatible controller
       product: GK107GL [Quadro K420]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
       configuration: driver=nvidia latency=0
       resources: irq:128 memory:de000000-deffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:c0000-dffff

Also, the result of xrandr:

Screen 0: minimum 8 x 8, current 3840 x 1162, maximum 16384 x 16384
DVI-I-0 connected 1920x1080+1920+82 (normal left inverted right x axis y axis) 598mm x 336mm
   1920x1080     60.00*+
   1680x1050     59.95  
   1600x900      60.00  
   1440x900      59.89  
   1280x1024     75.02    60.02  
   1280x800      59.81  
   1280x720      60.00  
   1152x864      75.00  
   1024x768      75.03    70.07    60.00  
   800x600       75.00    72.19    60.32    56.25  
   640x480       75.00    72.81    59.94  
DVI-I-1 disconnected (normal left inverted right x axis y axis)
DP-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 673mm x 284mm
   1920x1080     60.00*+  59.94    50.00    60.05    60.00    50.04  
   1680x1050     59.95  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1280x720      60.00    59.94    50.00  
   1152x864      75.00  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x576       50.00  
   720x480       59.94  
   640x480       75.00    59.94    59.93  
DP-1 disconnected (normal left inverted right x axis y axis)
  2560x1080_60.00 (0x31c) 230.000MHz -HSync +VSync
        h: width  2560 start 2720 end 2992 total 3424 skew    0 clock  67.17KHz
        v: height 1080 start 1083 end 1093 total 1120           clock  59.98Hz
  2560x1080_50.00 (0x326) 188.750MHz -HSync +VSync
        h: width  2560 start 2712 end 2976 total 3392 skew    0 clock  55.65KHz
        v: height 1080 start 1083 end 1093 total 1114           clock  49.95Hz

Any help is much appreciated.

Do you have a pure DisplayPort cable without any adaptors? e.g. DisplayPort output from graphics card to DisplayPort input on monitor? Just wondering as normally a DP or HDMI monitor would report all it's supported resolutions to the OS. But obviously your xrandr output shows it does not seem to be doing that with a reported max resolution of 1920x1080 — codlord, Jun 15 '20 at 10:34
Thanks for asking. I forgot to mention that I used an adapter that converts from HDMI to DisplayPort. Both of my monitors only have HDMI ports. — quangtrank9, Jun 15 '20 at 10:49
I think that's probably why it's not reporting/allowing the correct resolutions by default then. You may be better off trying a different adaptor or DP to HDMI cable as it may be that your current method does not support certain resolutions or at least does not seem to support the correct DP/HDMI standards. — codlord, Jun 15 '20 at 10:55
Thank you for your suggestion. I have tried with a different adapter but the problem persists. In addition, I used the same adapter for Windows. I think the problem lies in the fact that I cannot add a new mode to xrandr. What happens after that, I have not had a chance to verify. — quangtrank9, Jun 15 '20 at 10:58
I have never used xrandr to add resolutions so I can't advise, but what about these topics? https://ubuntuforums.org/showthread.php?t=2324211 or https://unix.stackexchange.com/questions/387735/how-to-set-a-custom-resolution-with-nvidia-drivers-installed — codlord, Jun 15 '20 at 11:27
I have tried both but the error still persists and I tried to add mode to xrandr — quangtrank9, Jun 15 '20 at 12:52
Did codlord suggestion functioned? If yes, please mark his as correct answer. — Marcelo Scofano Diniz, Dec 06 '20 at 13:19

score 0 · Answer 1 · answered Jun 15 '20 at 09:51

I would edit your question above your results from running xrandr and lshw -c video so people can see more details of your setup.

I have 2 of this sort of LG ultrawide (not sure on the exact models) on one PC, but have never had any issues with Ubuntu (personally I don't use any proprietary drivers), they have just been detected and worked without any custom settings.

I don't know if my output from xrandr showing the two LG monitors will help you determine compatible settings for adding a custom mode?

HDMI-1 connected 2560x1080+0+1080 (normal left inverted right x axis y axis) 673mm x 284mm
   2560x1080     60.00*+
   1920x1080     60.00    50.00    59.94  
   1920x1080i    60.00    50.00    59.94  
   1680x1050     59.88  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    60.00    59.94  
   720x400       70.08  
DP-1 connected primary 2560x1080+0+0 (normal left inverted right x axis y axis) 798mm x 334mm
   2560x1080     60.00*+
   1920x1080     60.00    60.00    50.00    59.94  
   1920x1080i    60.00    50.00    59.94  
   1680x1050     59.95  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    60.00    59.94  
   720x400       70.08

Thanks a lot. I added that part. – quangtrank9 Jun 15 '20 at 10:12 — quangtrank9, Jun 15 '20 at 10:12

score 0 · Answer 2 · answered Apr 26 '21 at 17:26

0

I had to install drivers. "Windows" key -> type "driver" and select "Additional drivers". Then choose the one that says "tested" (screenshot in link). Then restart.

driver to install

answered Apr 26 '21 at 17:26

justin

101

Ubuntu 20.04 cannot reach resolution 21:9 with an ultrawide monitor

2 Answers2