GTX 760, no doubt. With new drivers will come better performance, and there are only a few situations that the 660 Ti barely edges the 760. Plus, the 760 is ~$30 cheaper.
i will buy the above beast then ??? check all the specifications in that link n let me know please . there is something like REV 2.0 for this product what does that mean ? there is another gigabyte one which doesnt have REV 2.0