Is 650 ti or 7790 or 260x better? All around the same price
GTX650ti and GTX650ti with Boost is 2 different things.
And performance is a much bigger step up. There are also a few more improvements made in the 650ti boost like SLI capable if you have the correct mobo to do so.
To give you a better understanding, GPU does not really go seeing price range.
According to what MoneyFace have showed you in graphs, i will give you a better view on how are the new cards stacks. Is just a rough guideline and also very much depending on what games and applications you use. I will only include current cards that are available in the market.
7750/R7 250 < GTX650 < 7770 < GTX650TI < R7 260X/7790 < 7850/GTX650ti Boost < GTX660/7870 non tahiti < 7870 Tahiti/R9 270X < 7950 < GTX760 < GTX770/R9 280X < R9 290/GTX780 < R9 290X/Titan < GTX780Ti