What is better between amd radeon hd 7770 1gb or nvidia geforce gtx560 ti 1 gb superclocked

They are extremely close, the nVidia wins by 4x the bandwith in memory speed, but the 7770 has a higher core clock and twice the stream processors. I would go with the 7770, from what i've heard, there is almost no room for further overclocking on the 560, while the 7770 has achieved much higher stable overclocks that even 1.1 GHz, even without over clocking I beleive the 7770 would be faster.