How to Check the Signal Cable on a PC

By Stephen Lilley

The "signal cable" is a term used to describe the cable that connects your computer's case to your computer monitor. It was given this nickname (its real name is a VGA cable) due to the fact that if you have any problems with the cable at all, such as the cable becoming loose or unresponsive, the phrase "No Signal" will display on your monitor alerting you to the problem. You will also see this message occasionally if your computer video card is malfunctioning and cannot send the proper video signal through the cable to your monitor. If you want to check to make sure your PC's signal cable is working properly, there are a few different things you can do depending on what type of equipment you have available to you.

Step 1

Check to see that your signal cable is securely plugged into both your computer and your computer monitor. The plastic plug on each end of the cable should be plugged firmly into each device. If you were to press on the plug on the end of the cable and push it toward the device, the plug should not move if it is inserted into its hole all the way.

Step 2

Try using your signal cable with a different monitor. If you have a different monitor available in your home (perhaps from a second computer or an old computer you don't use anymore), plug it into your computer as opposed to the monitor you are currently using. If you continue to receive a "No Signal" message on screen, then the problem lies with your original computer monitor and not your signal cable. If that second monitor does not work as the first one didn't, you have a problem with the signal cable and it will need to be replaced.If your monitor troubles are related to a hardware issue, you will see the familiar "No Signal" message on screen. If everything works correctly while testing the second monitor, you will see the regular computer desktop on screen.

Step 3

Try using your signal cable with a different computer. If you have an older computer in your home (or have any kind of access to a second computer), try plugging your existing monitor into it. You don't have to hook up the keyboard or mouse or any other peripheral devices. Simply plug the computer's power cable into a wall, connect the signal cable to the back of the computer and turn it on. If you continue to receive a "No Signal" message on screen, then the problem lies with your computer's video card and not your signal cable. If that second computer does not work, you have a problem with the signal cable and it will need to be replaced.If your monitor troubles are related to a hardware issue, you will see the familiar "No Signal" message on screen. If everything works correctly while testing the second computer, you will see the regular computer desktop on screen.