Cygnus x-1 said:
Well the main Pro for the 6850 is it's the faster card out of the three. It should be comparible in temps and voltage to the 5770, so that should be a pro as well. Only con is it will use more power than the 6790, but if you planning on gaming you don't want the 6790 with a decent monitor anyway.
I don't think you know what you are talking about, the HD 6790 actually uses MORE power than a HD 6850.