New GPU advice

[/\ndy]

Hello

Looking to upgrade my existing rig, specs:

MSI H67MA-E45 Intel H67
Intel Core i5-2500 3.30GHz (Sandybridge)
MSI ATI Radeon HD 5850 1GB
BeQuiet Pure Power L7 530W '80 Plus' Power Supply
Corsair Vengeance Pro Blue 8GB (2x4GB) DDR3

I play occasional games at no more than 1080p, although would like the option to game at 1440p in the near future.

I think the only component which bottlenecks this is my graphics card, unless any of you think otherwise?

Any card suggestions? 780Ti? GTX 970? Or are these overkill?

 

[/\ndy]

£250 at a push

 

[/\ndy]

Still get warranty with b grade?

*edit 90days