Old monitor screen 'quivers'?

Infopackets Reader "Rayla Wolff44" writes:

" Dear Dennis,

Our computer monitor stopped working, and so we ended up borrowing our daughters old monitor and plugged it into our machine. The old monitor worked fine on her computer, however, when it's plugged into our machine, the icons appear to 'quiver' some times. What do you think is causing this problem? "

My response:

I have a number of suggestions off the top of my head.

If the 'quivering icons' was a problem with your old monitor, then it is possible that the problem lies with your video card. If not, then try moving around the cable that goes from the monitor to the computer, as you might have a short in the cable.

Also, check for any other electronic devices nearby which may be causing interference (such as a telephone or stereo). I could also be that the monitor is just plain old and is on its way out.

You can also try adjusting the refresh rate on the monitor to see if that helps. To adjust the refresh rate, click Start -> Settings -> Control Panel -> Display, then go to the Settings tab -> Advanced button, then to Adapter, and change the refresh rate to 72 or 75 Hz. If the monitor is really old, it may not be able to handle the new refresh rate, but Windows should default back to the previous setting (60 Hz) within 15 seconds if the screen becomes unusable.