Like this:
$ xdpyinfo | grep -A3 ^screen
screen #0: dimensions: 1280x800 pixels (331x207 millimeters) resolution: 98x98 dots per inch depths (7): 24, 1, 4, 8, 15, 16, 32
Like this:
$ xdpyinfo | grep -A3 ^screen
screen #0:
dimensions: 1280x800 pixels (331x207 millimeters)
resolution: 98x98 dots per inch
depths (7): 24, 1, 4, 8, 15, 16, 32