the actual clock speed in software is said to be 400mhz.
Its ddr3 , then its Memory Mhz x 3, x 2, or how ?
not how memory works.
i dont know exactly how it works in videocards actually. Effective clock speeds are different than what you see on screen because of the bit interface and pcie interface. your effective clock speed goes up if you oc the clock speed on screen, effectively giving you better bandwith and speed to communicate with your mobo and cpu