Please give some information about the monitor...manufacturer, model, LCD or CRT? I don't know if changing the refresh rate is the answer but I'm sure other members will be along to give you some help.
I doubt the article at Smart Computing for Fight Flicker will be of much help especially since you have to be a paid subscriber there to view the article.
To view the full text of any article published in Smart Computing, PC Today, First Glimpse or Computer Power User magazine, you must be a
paid subscriber to one of these publications.