I was unable to find anything in your MB manual about multiple video cards.
Matt had a good suggestion. Basically he says to remove the drivers and reboot.
Here's how:
Go to control panel>system>hardware>device manager>display adapters
Right click on each one of them and uninstall. Shutdown your "puter. Put the third card in it and boot up. Windows should install all three cards at this time.
Hi msufan, I think that you are going to find that this is a driver problem. I think I would send a email to the company to see if they have a driver that will run two of their cards and four monitors.
Hi msufan, it sounds like you have the display system I'm trying to put together. I was wondering how your ASUS AGP 5600 card compared to this card for price and onboard memory. http://www.accupc.com/itemDetail.jsp?pid=vpcar764p