GuiguiBaah,
Is there any chance that you KDS monitor is still under warranty?
If it's a CRT, they usually carry a 3 year warranty.
If you're not sure how old the monitor is, there is probably a label on the back with a "Date of Manufacture", or call KDS Tech Support (800-283-1311), give them the serial number, and they can determine the warranty status.
Here's the web page for KDS's Warranty Information:
http://www.kdsusa.com/supports/warrantyInfo.asp
The company that I work for had bought a number of KDS monitors, and I've had to have several of them replaced while under warranty. KDS Tech Support and Customer Support are very easy to work with.
If your monitor is indeed still under warranty, you can probably get it replaced for the cost of shipping the broken unit back to KDS. KDS will then send you a new or refurbished monitor of the same or equivalent model.
Hope this helps.