Could be the textures in the game, try doing a repair install of vindictus or a complete re-installation of the game. If that doesn't work I'd take the video card out of the pc and return it for a GTX670!! I'm kidding. But take the card out of the computer, uninstall any AMD Catalyst drivers. Then mount the card again, install the absolute latest availible drivers for the 7950 and you should be good. If you still have that problem see if theres any tech support for the game, and ask them if they have encountered any texture problems? If they say no then go to the store a buy the 670.
lol i swear i was posting that the same time you were i just had to take a phone call so post got delayed