hmmm and this card worked fine with another os or not, who's the manufacturer of it maybe check their website for drivers as sometimes manufacturers do not stick to amd/ati's design plan and require drivers from the manufacturer instead sorta like mobile video cards in that respect, although most radeon 9600 pro cards are almost the exact same thing just a different HSF and stickers and a name in the bios but thats usually as far as it goes from the stock ati design but on the rare occasion they do do other stuff like clocking and fan speeds yadda yadda thats why i say check their website or you could just go back to 8.11 or 8.10 vista drivers i know they work failing that take the card out of the system and reinstal it maybe its just a seating issue bad contact can cause issues like this
Operating System Windows7 X64
Computer Type Desktop
CPU Type and Speed AMD Phenom II x4 940BE @ 3.0GHz
Motherboard Chipset Asus M3A32MVP-Deluxe
System Memory Type 4GB Corsair Dominator Twin2x2048 PC8500 x 2 kits DDR2-1066
Video Card Type and Speed HIS HD5770Fan 1GB DDR5 930/1250MHz
Computer Monitor AlienWare OptX AW2210 21.5" LCD
Hard Drive 2x WD2500AAKS raid0 boot, 3x Samsung HD502IJ storage
Optical Drives Pioneer DVR212S 18x DVDrw
Network Adapter Marvell Yukon 88E8056 PCI-E Gigabit Ethernet Controller
Anti-virus Software MSE
Computer Skill Level Self-Taught Expert
Windows Experience Index 5.9