I currently sold my my 260x and my x360 and my budget for new gpu has became bigger the first gpu that come in my mind was gtx660ti but now that I have more money what should I buy a gtx 680 or gtx 770 and why?
You will get fair price/performance at every price point with midrange graphics cards.
My take is to buy a newer gen Maxwell based card that is more power efficient.
A 500w psu will run one as strong as a GTX970 or even GTX980.
On the AMD side, a R9-280.
The GTX960 looks like a winner in your price bracket.
Check out the reviews.
You will get fair price/performance at every price point with midrange graphics cards.
My take is to buy a newer gen Maxwell based card that is more power efficient.
A 500w psu will run one as strong as a GTX970 or even GTX980.
On the AMD side, a R9-280.
The GTX960 looks like a winner in your price bracket.
Check out the reviews.
The 770 is better, but if you want a new card, the 960 is almost identical and uses less power. However the benchmarks between these two bounce up and down. Personally I would get a better PSU and buy a 280x.