Dell U3014 Monitor - Manual (Page 39)

Icon Menu and
Submenus Description
Brightness/Contrast Use this menu to activate Brightness/Contrast adjustment.
Brightness Brightness adjusts the luminance of the backlight.
Use the button to increase brightness and push the button to decrease brightness (min 0 ~ max 100).
NOTE: Manual adjustment of Brightness is disabled when Energy Smart or Dynamic Contrast is switched On.
Contrast Adjust Brightness first, and then adjust Contrast only if further adjustment is necessary.
Push the button to increase contrast and push the button to decrease contrast (min 0 ~ max 100).
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.