How to turn on a computer monitor or another display

Updated: 06/02/2020 by Computer Hope
Computer monitor with a blank screen.

The following page contains information on how to turn on a computer monitor and other displays, including a laptop display and a projector. Follow the steps for the display you're trying to turn on.


If your monitor has worked in the past but is no longer working, see: No display or black screen on a computer monitor.

How to turn on a computer desktop monitor

LCD monitor

Before a monitor can be turned on, it must be connected correctly with the power cord and data cord. If you're unsure about how to connect a monitor to a computer, see the following page.

Locate the monitor power button

Once a monitor is connected to the computer, the next step is locating the power button. Unfortunately, there is no standard for where a monitor power button is placed but should be in one of the following locations.

  • The front of the monitor, below the screen, commonly on the bottom right corner.
  • The top or bottom edge of the monitor, commonly on the top-left or bottom-right side.
  • The Left or right side edge of monitor.
  • Bottom center of the monitor.

When the monitor power button is pressed correctly on a properly connected monitor, an LED (light-emitting diode) on the monitor should illuminate. If the computer is powered on and sending a signal, a picture on the monitor should be seen.

If pressing the power button does nothing, make sure the power cable is firmly connected to the back of the monitor and the computer. If the cable appears to be firmly connected and it's connected to a known good power outlet, the monitor is likely defective.

How to turn on a laptop display

Laptop display

A laptop display should turn on with the computer. If the computer is turning on (power light turns on), but the screen remains black, there may be a problem with the display. See the following links for troubleshooting help with no laptop display.

How to turn on a projector connected to a computer

Digital projector

All projectors have a power button for turning the projector on and off. For most projectors, the power button is either on the top or back of the projector. When pressed properly, a fan should begin to run inside the projector, and a power indicator light may be visible. Once the projector is running, slide the protective cover on the lens to start projecting the computer's image.