Sony Bravia and GTX 660

Hello,
I recently built a gaming computer boasting a gtx 660 for my living room(As a replacement for a console). when i hooked it up to my 46'' bravia tv, and played Fallout New Vegas, Skyrim, And Assassins Creed 3, they all automatically adjusted contrast and other display settings automatically. I've poured over the internet and my user manuals. Any solution presented to me seems to not do anything. I have ran out of ideas and would appreciate some help.

Thanks!