I've been trying to update my driver, but I get an error.

My graphics card is an AMD Radeon HD 6900m. I got the the official website and download the autodetect tool. It finds my graphic card and download the corresponding file.
But when I run the downloaded file, it says that it cannot be downloaded due to incompatible hardware/software on my computer.

I have an Alienware M17x.

Please help me. I really need to update my driver so I can run Skyrim smoother.

Edit: The latest driver on Dell's website is from 7/29/2011.