Sounds like a good plan the. I might suggest instead of using 2 graphics cards in cros-fire instead buy one current gen one. Not only will you have the latest version of direct x 10.x whatever the x num is lol but you also wont be hassled by programs that dont sopport dual gpu's very well...
Both ati and nvidia have some awesum new cards out that will out pace those 2 in cross fire and cost around the same.
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