the only thing I would highly recommend, is to buy an NVidia card and not a ATI X800 or similar.
We had a lot of trouble and one almost sleepless night because of the shitty ATI driver on a bigger installation apprx. two weeks ago. The problem was to set the card to a special resolution of 2x 1400x1050 with 50Hz in Horizontal Span Mode over DVI output.
OK … this sounds very special, but with the two NVidia 6800GT we bought the next morning it was only a few mouseclicks … quasi plug and play.