Oh also, even though a card is a part of a numerical series, it does not mean the card is actually of he same chipset series. Nvidia and ATI are really bad a taking an older chipset doing a mild overclock and calling it a member of the next series up. The 500 series is the Fermi chipset, which has some issues with running hot. The 600-700 series is based on the Kepler chipset architecture that runs faster and cooler than Fermi. The rub is that The 650 and below aren't Kepler, they're Fermi with an OC. If you see a 600 or 700 series card for a steal, dig deeper and you'll be surprised what you find. There's a reason it's cheap. Just do your research and you'll be fine. HardOCP, Tom's Hardware and Anandtech are probably the most mainstream sites out there. Good luck!