the gtx260 is slightly faster than the 5770 but personaly i would get neither. for the same money ($194.99) i bought a XFX HD 4890 from amazon.
the 4890 will run circles around the other 2 cards. the only good thing about the 5770 is that it supports directx11 and eyefinity, which is pointless because it is too weak to run the few games that support dx11
the gtx260 supports physX but still, rather something a bit better like a 4890
Well see the problem with the amazon idea is that i HAVE to buy it from newegg which i should probably have stated in the first post i made. As for PSU/CPU etc here is the bundle i am getting from newegg it has everything except gpu (which im picking out as you can see) http://www.newegg.com/Product/ComboBundleDetails.aspx?I...
I would skip past the 5770 and get the better performance that either of the cards above offer. The 4890 outperforms a stock GTX260, however with the OC on this card it puts it similar in performance to a GTX275, which is comparable to a 4890. If you plan to overclock, the 4890 will have more headroom though.