I ran a 9700 pro in my shuttle cube and never had a problem. Truly, give the ATi cards your consideration.... I know for a fact they work well and that there is no problem with space or power consumption while running two hd's, and a cdrw/dvd. I even had a pci card in drawing a bit extra power, too. No problems whatsoever with an SN41g2.
Sony Zeiss 55/1.8 SSM, 24-70/4 SSM
Minolta 17-35/2.8-4 D, 100-300 APO, 100/2, 500/8