Facing an issue with how to change the screen resolution for your newly setup Ubuntu server box? Here is the simple guide on how to change the screen resolution.

The following table lists some of the available VGA codes for changing of screen resolution purposes.

VGA Resolution Codes for GRUB & Lilo

Depth 640×480 800×600 1024×768 1152×864 1280×800 1280×1024 1440×900 1600×1200
8 769 771 773 353 864 775 868 796
16 785 788 791 355 ??? 794 ??? 798
32 786 789 792 ??? 865 ??? 869 ???

To change the screen resolution, let’s start by updating the grub file.

sudo nano /etc/default/grub
or if you prefer vi then
sudo vi /etc/default/grub

Look for the line of CRUB_CMDLINE_LINUX=. To set the screen resolution to 800×600 for 8 bits of color depth, we will need to enter vga code 771 as the following.

CRUB_CMDLINE_LINUX="vga=771"

Save the changes to the file. Then, run the following command to update the grub.

sudo update-grub

Restart the system now and you should observe that the screen resolution has changed.

sudo shutdown -r now