If the monitor is on, and you do not see a power LED (blue, green, or orange light) on the front of the monitor, press the power button until it comes on. If no light comes on after several attempts, make sure the connections are properly connected.

If your computer monitor was on and you stepped away from the computer, then upon returning, it was black, it is likely that the computer is asleep. Try moving your mouse, clicking the mouse buttons, or pressing any key (eg, spacebar) on the keyboard to wake it up.

If the data cable is plugged in, make sure the monitor is getting power by verifying there is a light (blue, green, or orange) on the front of the monitor.

If you see no lights on the monitor, make sure it is connected to a working wall outlet. If the power cord is removable from the back of the monitor, try replacing it with another power cable. If you still cannot power on the monitor after trying another wall outlet and cable, the monitor is bad and should be replaced.

If the monitor has a light on the front, but that status light is orange or flashing, make sure the monitor is not in a suspend mode by moving the mouse or pressing a key on the keyboard. If this does not help, turn the computer and monitor off and reconnect the data cable on the back of the computer and, if removable, on the back of the monitor, turn the computer and monitor back on.