Without going into too much detail here, both HyperMemory and TurboCache technologies attempt to do the same thing. Using the north bridge of the core logic chipset that usually controls the memory (except for the case of AMD's Athlon 64 processors), ATI's X300 SE HyperMemory GPU can directly address system memory for frame buffer usage, just as the TurboCache technology allows the 6200 TC cards to do the same.



Link: PCPer