This may help to explain the problems people here have been having with their NVidia cards- especially the 8800 series. http://www.xbitlabs.com/news/video/d...208235331.html
Hundreds of end-users reported complaints about instabilities, erratic behaviour, driver bugs and other kind of issues that they faced because of Nvidia's ForceWare drivers designed for Microsoft Windows Vista. End-users with various graphics cards, including the latest top-of-the-range GeForce 8800-series, criticized Nvidia ForceWare for poor performance and stability, something, that the logotype "Vista Ready" is not meant to say.
They are talking about issues with Vista, but the issue appears to apply to other applications too like this game.Nvidia, according to InformationWeek web-site, has acknowledged that its Vista drivers have not performed as well as they should, and said in an e-mail that driver development for Vista is "the highest priority in our company".
"We are working diligently to make sure we achieve and maintain the level of driver quality and reliability that Nvidia is known for. Over the coming weeks, Nvidia and our partners, along with the industry will continue to update Windows Vista drivers to ensure maximum performance on 3D applications and add feature support," Brian Burke, public relations director of Nvidia said.