I already know that HD7770 is better than GTX650 and GTX650 Ti is better than HD7770, but are the difference in performance noticable between GTX650 Ti and HD7770? Is the GTX650 Ti worth the extra bucks?
Scroll through those benchmarks, you'll see around a 10-18% increase in fps, depending on the game (sometimes less, sometimes more, see DiRT showdown vs BF3).