Lost Planet (DirectX 10)
Lost Planet is a 1st or 3rd person shooter that was out originally on the Xbox 360 but then made the transition to a DX9/DX10 title for the PC this summer. Set in a frozen world where you have to kill the opposing aliens in order to sustain enough heat to stay alive, Lost Planet has some visually impressive settings that make it a good benchmark title.
There are few DX10 settings that you can enable to adjust for which shader path you would like to use that are only available on Vista when a DX10 card is detected.
The 8800 GT 256MB card puts up a good fight here but falls to the HD 3850 256MB card once again, though the gaps are somewhat smaller. Even more noticeable is the gap between the 512MB and 256MB versions of the 8800 GT making the 512MB model that much more impressive looking.