When using old televisions as monitors, the screen will not display correctly due to overscanning, where the television sets the visible area to be smaller than the image sent it. In some TV's, this can be modified in its configuration by looking for “overscan” or even telling it the input is a computer. In other cases, we must have Unix adjust the screen so the entire desktop is visible on the television.

Assuming we are set for 1920×1080, the following is a good starting point. We are using xrandr to transform the desktop to 1800×1000, then moving the x and y axis -60 and -30 respectively.

xrandr --output "HDMI-1" --fb 1800x1000 --transform 1,0,-60,0,1,-30,0,0,1

Note: you will get an error message about the specified screen size being too small for the output. That is because we are defining a screen smaller than the resolution. you can safely ignore this message.

A full discussion is available at https://superuser.com/questions/1435053/how-to-use-xrandr-to-crop-part-of-my-monitor#1495587