Sometimes PC monitor it self become faulty, even if your not doing anything to it, you need to make several efforts to get it back in functioning order or seek the remote PC support services for assistance. When the computer's monitor does not work well, it may due to several reasons such as electrical and cabling issues, a problem with the video adapter of your machine, or a problem with the drivers. Remember no matter what you do, never try to open up the monitor while it is plugged into an outlet, as monitors use high voltage and can be dangerous; if you are not sure, always get an authorized computer troubleshooting technician to help you.
If you decide to start troubleshooting yourself, you may check to see if there are any loose electrical cables. Try removing the electrical cord from the back of the monitor and then place it back to see if there are any changes. If that does not work, you may remove the VGA cable from your monitor and machine and then again put it in place. In case you are using a cable extender, make sure you do away with it.
