Don't know of anything I did to cause this, so I don't know what to do. Here's what I must fix: I have two monitors, Viewsonic Model VA2226w, one connected to the analog output, the other conn. to the other output (using a converter to connect the Radeon's digital output to the second monitor). The secondary monitor has worked for months successfully. Just the other day it became yellow where white should be. I can't get it to be white.

Can anyone suggest a fix?