They overclock the cards and thos settings are flashed in the BIOS. They normally offer better cooling to go with this and the warranty covers these overclocked settings. Sometimes the use faster ns RAM too. But yes, you can buy a normal card and overclock it yourself. Just read some reviews on various brands to see what one would have a good cooling solution that will let you overclock without aftermarket cooling. Most of the time its not worth the extra to get an overclocked card, especially not for 15mhz extra like some manufacturers offer. Rather than getting an overclocked version you better off just getting the next model up. If your motherboard is able to run crossfire you would be better off just getting another 5770.