Amd X6 and Nvidia graphics card question

I have recently built a new computer and I was talking to a friend about getting a graphics card. I told him I was looking into the nvidia gtx 460 and he told me that only the ati cards take full advantage of the new phenom x6 cores or something like that. I was rather skeptical and im not sure if he misunderstood my intentions or whatever. Anyways a straight forward answer from someone who knows would be great. Thank you very much.

PS This is a singular graphics card I am not looking into SLI(especially since its a Cross Fire board)

My computer

AMD Phenom X6 1050t 2.8ghz
Asus M4a89GTD Pro Motherboard
No graphics card right now
and other specs arent too important for this question