How to Set A Custom Screen Resolution in Ubuntu Desktop

Is your screen (or external monitor) resolution is low? thus making the items on your screen look larger and less clear? Or do you want to simply increase the current maximum resolution or add a custom resolution?

In this article, we will show how to add missing or set custom display resolution in Ubuntu and its derivatives such as Linux Mint. By the end of this article, you will be able to set to a higher resolution, making content on your screen appear sharper and clearer.

Changing the Resolution or Orientation of the Screen Using Displays

Normally, to change the resolution or orientation of the screen, you can use the Displays graphical user interface tool (open the Activities overview and type Displays, click to open it or System Menu then type Displays and open it).

Note: In case you have multiple displays connected to your computer (as shown in the following image), if they are not mirrored, you can have different settings on each display. To change the settings for a display device, select it in the preview area.

Next, select the resolution or scale you want to use, and choose the orientation then click Apply. Then select Keep This Configuration.

Changing the Resolution or Orientation of the Screen Using Xrandr

Alternatively, you can also use the powerful xrandr tool (a command-line interface to RandR (Resize and Rotate) X Window System extension) which is used to set the size, orientation and/or reflection of the outputs for a screen.

You can also use it to set the screen size or list all active monitors as shown.

$ xrandr --listactivemonitors

To show the names of different outputs available on your system and resolutions available on each, run xrandr without any arguments.

$ xrandr

Set Screen Resolution in Ubuntu

To set the resolution for a screen for an external monitor named DP-1 to 1680×1050, use the --mode flag as shown.

$ xrandr --output DP-1 --mode 1680x1050

You can also set the refresh rate using the --rate flag as shown.

$ xrandr --output DP-1 --mode 1680x1050 --rate 75

You can also use the --left-of, --right-of, --above, --below, and --same-as options to arrange your screens either relatively to each other.

For example, I want my external monitor (DP-1) to be positioned left of the Laptop screen (eDP-1) in correspondence to the actual physical positioning:

$ xrandr --output DP-1 --left-of eDP-1 

Keep in mind that any changes made using xrandr will only last until you log out or restart the system. To make xrandr changes persistently, use the xorg.conf configuration files for Xorg X server (run man xorg.conf for details on how to create a xorg.conf file) – this is the most effective method.

You can also use the ~/.xprofile file (add xrandr commands in it), however, there are some disadvantages of using this method, one is that this script is read fairly late in the startup process, thus it will not alter the resolution of the display manager (if you use one e.g lightdm).

How to Add Missing or Set Custom Display Resolution Using xrandr

It is possible to add a missing or custom display resolution e.g 1680 x 1000 to Displays panel, for a specific display device (DP-1), as explained below.

To add a missing or custom display resolution, you need to calculate the VESA Coordinated Video Timing (CVT) modes for it. You can do this using the cvt utility as follows.

For example, if you need a horizontal and vertical resolution of 1680 x 1000, run the following command.

$ cvt 1680 1000

Next, copy the Modeline (“1680x1000_60.00″ 139.25 1680 1784 1960 2240 1000 1003 1013 1038 -hsync +vsync) from the output of the cvt command and use it to create a new mode using the xrandr as shown.

$ xrandr --newmode "1680x1000_60.00"  139.25  1680 1784 1960 2240  1000 1003 1013 1038 -hsync +vsync

Then add the new mode to the display.

$ xrandr --addmode DP-1 "1680x1000_60.00"

Now open the Displays and check if the new resolution has been added.

The above changes are only temporary and work for the current session (they last until you log out or restart the system).

To add the resolution permanently, create a script called external_monitor_resolution.sh in the directory /etc/profile.d/.

$ sudo vim /etc/profile.d/external_monitor_resol.sh

Then add the following lines in the file:

xrandr --newmode "1680x1000_60.00"  139.25  1680 1784 1960 2240  1000 1003 1013 1038 -hsync +vsync
xrandr --addmode DP-1 "1680x1000_60.00"

Save the changes and exit the file.

For more information on how xrandr works and how to use it, read its man page:

$ man xrandr 

That brings us to the end of this article. If you have any thoughts to share or queries, reach us via the feedback form below.