I've never done that particular set up myself but I know a couple guys that did it with ATI cards before. The usual recommendation is to buy a card with two vga (or hdmi since you say vga isn't good enough) ports. They produce less heat and use less power than two separate cards. I don't know of any cards off the top of my head with two dvi ports, but there are hdmi to dvi cables. Beyond that, you should be fine. If you do it and there is an issue, we will be glad to help you sort it out.