MarhyCZ :
Ok,but from this http://www.techspot.com/review/603-best-graphics-cards/ it seems that 7970 has better performance.When you look on BF3 or Skyrim...But yes they are similar.So which of these cards has better "stability" (less bugs,..)?And are technologies as a TXAA,..(i don´t count PhysX it´s not good technology) worth it?
Well, HD 7970 is much much more powerful gpu compute wise than GTX 680, if thats useful to you.
Nvidia has TXAA and FXAA, but its up to you to use it in the game. Both are not used as often. You get CUDA which is pretty good
Stability they are the same.
Really comes down to you preference. R7970 is cheaper and performs better. GTX 680 comes with a lot of bells and whistles. R7970 ghz will more likely overclock bette than gtx 680.
Oh yea, GTX 680 falls down a cliff for high resolution and high anti aliasing due its limited bandwidth.