When you connect a new monitor to Ubuntu, sometimes you get unknown display, and it only allow you select a lower resolution than what your monitor is capable of. You can made new resolution mode to your new monitor.
My new monitor is connected at DVI, and that’s why it’s called DVI-0 (the default DVI monitor).
- To get the name of the display, you can use the command: xrandr (this command will show the name of all the connected display, which you can use the names later to define and add new modes and resolutions.)
- To get the mode line you can use for the command –newmode, use this command: cvt 1680 1050 (the 2 number is the resolution I want to add, then the output will tell you exactly the mode line to use. For example:
- Then you can use the command to define the new mode: xrandr –newmode “1680x1050_60.00” 146.25 1680 1784 1960 2240 1050 1053 1059 1089 -hsync +vsync
- Then use the command to add new mode: xrandr –addmode DVI-0 1680x1050_60.00
- Finally, use the command line to add the new mode to a display: xrandr –output DVI-0 -mode 1680x1050_60.00
- However, this immediately change the resolution, but will not keep it after you reboot, so you need to add these commands to the startup file. Use command : sudo nano \etc\gdm3\init
- In the file, add these lines:
!/bin/sh
PATH=”/usr/bin:$PATH”
OLD_IFS=$IFS
xrandr –newmode “1680x1050_60.00” 146.25 1680 1784 1960 2240 1050 1053 1059 1089 -hsync +vsync
xrandr –addmode DVI-0 1680x1050_60.00
xrandr –output DVI-0 -mode 1680x1050_60.00
