Hello guys, I'am using dual monitor setup with a radeon 5770 vga card, also I have an onboard vga card on ASUS M4A785TD EVO mainboard. Now I want to add one more monitor to my system. Can I use the onboard vga for third monitor or I need to buy a new vga card? If I need to buy new vga card which one would you suggest for least price? I am using windows 7.