I've read that artifacts you seeing may be fixed by disabling "HZ buffer". This is done by setting registry key named An6aYj2vwKuKd9brxl7 under \OpenGL\Private of type REG_DWORD to 0. Also this file may help you with that
http://www.nvworld.ru/temp/HZDatabase.rar I'm not sure if it has russian text inside. At least you can get correct path in registry from it.
