Dell AW2210 Monitor - Manual (Page 17)

Brightness Brightness adjusts the luminance of the backlight.
Contrast Adjust Brightness first, and then adjust Contrast only if further adjustment is necessary.
The Contrast function adjusts the degree of difference between darkness and lightness on the monitor screen.
INPUT SOURCE Use the INPUT SOURCE menu to select between different video signals that may be connected to your monitor.
Auto Select Select Auto Select to scan for available input signals.