In this tip, we will see a command line utility called "xrandr" that allows Linux users to know the current screen resolution as well as your minimum and maximum screen resolutions.
Launch the terminal (Ctrl + Alt + T) and run this command:
xrandr -q | grep -w Screen
Here are the results I got for my screen:
Screen 0: minimum 320 x 240, current 1680 x 1050, maximum 1680 x 1050
Another command has the same function, but it also displays your screen refresh rate:
xrandr --verbose | grep *current
I got this:
1680x1050 (0x161) 88.2MHz *current
If you want to change your screen resolution with this command line utility (xrandr), then run this command:
xrandr -s 1024×800
Replace '1024x800' with the desired screen resolution.
This command is tested under Ubuntu 11.04 / 10.10 / 10.04