Dell offers a wide range of LCD monitors for different viewing purposes. Most of the monitors include built-in devices to control the color, contrast and brightness of the screen. Ambient light can affect how well you see the screen, while certain images or videos may require a brightness adjustment. Use the buttons on the front panel to adjust the Dell 24" LCD monitor to suit your viewing needs.
Turn on the monitor.
Locate the "-" button. It should have a small picture of a half white/half black sun below it.
Press the "-" button to display the "Brightness" and "Contrast" menus.
Press the "+" or "-" buttons to toggle the screen brightness up or down.