Upgrading Bootcamp Video Drivers Imac 27" (Late 2012)

I read everywhere that people have been able to upgrade the stock video drivers that apple include with Bootcamp (Version 306).

I have been looking for a way to upgrade them to beta version 310.77 or higher but so far, no luck. Could someone please tell me how to do it? Where do I download them from and so forth?

Any help will be greatly appreciated.

Huh. I downloaded drivers from the nvidia website, but the ones I downloaded apparently for their desktop chips gimme a "cant find compatible hardware " message whenever i try to install them. If i try and look for laptop beta drivers, all i get is an automated scanning tool on their website that wont gimme an option for downloading beta drivers.

I am sure given the responses that i am missing something.