Could you link the website where you will be buying your components? A list of all your components, your budget and computing needs would help, too.
The problem (I suppose) is the price differences we are weighing. In the USA, the GTX650ti is roughly the same price as the HD7850. And the GTX650ti costs 50% more than the HD7770.
The other problem (I suppose) as pointed out by Big Cy, is because of the 128-bit interface both cards begin to *choke* at 1080p. This is much less an issue at 1600x900 and below.
Over-clocking doesn't help as much as it potentially could on the cards because of the 128-bit memory bandwidth.
here r my configs-
my system config is .....
Intel(R) Core(TM)2 Duo CPU E7300 @ 2.66GHz
Mainboard Model gigabyte G31M-S2
4gb ram ddr2
cabinet- iball mtstique
might upgrade system if ite cpu starts bottlenecking in games.
i am getting 7770 for rs8400 from local dealer, recent saw the link of 650ti at rs9400 in nvdia site.http://www.nvidia.in/object/geforce-gtx-650ti-graphics-card-launches-20120509-in.html