Yes it could be. You should try a new monitor cable. Sounds like one of your sync pins is messed up. Is it possible for you to use the cable from the working monitor, or are both sealed up inside the monitor?
If you post what types of monitors you have, it may help.
*Edit
I think it is important to remind you that some VGA connectors do not have all 15 pin holes occupied with pins since all of tham are not needed. You may still want to reduce the refresh rate to 60 Hz and the resolution to 800x600 when attempting to get the monitor to work.
Has this monitor worked before? Can you verify that it is a broken pin?