I know this question has been asked at least twice, but I downloaded the 64-bit version of Ubuntu onto my Raspberry Pi 4. I looked at a few tutorials but I couldn't find anything that worked for changing my screen resolution. It decided to set my resolution to 1824 x 984 (9:5) I have no clue how to fix this. Could the smart people of AskUbuntu please help me? I have the official version from the Ubuntu website. I have used lsb_release -a to find my version and it says I'm using Ubuntu 18.04.4 LTS. I have used xrandr but the results are very strange:

ubuntu@ubuntu:~$ xrandr
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1824 x 984, current 1824 x 984, maximum 1824 x 984
default connected primary 1824x984+0+0 0mm x 0mm
   1824x984       0.00* 
ubuntu@ubuntu:~$ xrandr --output default --mode 1920x1080
xrandr: cannot find mode 1920x1080

What do I write as the display? I have never used Ubuntu before and help would be appreciated. I don't even know how to change the file /boot/firmware/usrconfig.txt

  • Please click edit to let us know which release number? Please do not use Add Comment; Comments are a channel from us to you, whereas the Question should contain all the facts you have about the issue.
    – K7AAY
    Mar 8, 2020 at 22:57

2 Answers 2


I had this problem and this is how I fixed it. Open a terminal window and type

    nano /boot/firmware/usercfg.txt 

(note you will need to run it with sudo, alternatively use any text editor). Then you can add the settings to set display resolution. Mine looks like this:

    # Place "config.txt" changes (dtparam, dtoverlay, disable_overscan, etc.) in
    # this file. Please refer to the README file for a description of the variouszn

    # configuration files on the boot partition.



Note the two groups HDMI:0/1 this is because RiP4 has two hdmi outputs and they can be configured individually. Also see that the hdmi_group=2 refers to computer monitors, 1 would be for television screens. hdmi_mode=82 refers to my resolution which is 1080p 60Hz. To find a full list of mode numbers that corresponds to resolutions and rates, you can go here:


Refer to hdmi_mode section.

Once these changes are made, you can restart.

  • This doesn't work for me. I had to use xrandr add mode and newmode calls to add a new resulution and activate it.
    – bre_dev
    May 27, 2021 at 17:47
  • Worked, but the display contrast became low. The background black turned into a white-ish black, and I haven't understood why. Maybe something to do with scaling? Anyone know?
    – KIYZ
    Jan 25 at 4:03
  • Can confirm this solution still works for Ubuntu 20.04.
    – wyphan
    Mar 11 at 21:31

You can use:

% xrandr -q  

to list the available modes to pick from.

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