I have the MSI 460 786mb.
I have not paid attention to gfx cards in some time and was wondering which of these I should upgrade to.
EVGA GeForce GTX 570 HD Fermi 732MHZ 1280MB
Gigabyte GeForce GTX 660 OC 1033MHZ 2GB
Out of those 2, I would go with the 660. It is a little bit faster and not to mention less noise and power. But if you could stretch your budget or wait for a good sell and get the 7870, that would be even better. Actually, I think you can find a decent 7870 for $230.