The GTX 650 Ti was designed to replace the GTX 550 Ti and is much slower than your GTX 560 Ti. ARNOLDLOUIE is completely right.560 Ti vs 650 Ti
The 560 Ti dominates in every single benchmark except DX11.
Here you see the 560 Ti is roughly 12% faster overall. You wouldn't "see" an increase in performance until you get around the GTX 570, Radeon 7870 or GTX 660.