The first generation of HyperMemory paired ATI RV370 with 32MiB of on-board memory on a 64-bit memory bus. That configuration then augmented a further 96MiB of system to create a 128MiB product. Our analysis of the first Radeon X300SE HyperMemory products, carried out by yours truly, presented a conclusion that performance was solid, but generally bested by NVIDIA's comparable TurboCache offerings.

And that's all we've seen of HyperMemory until recently, when PowerColor dropped an RV515-based HyperMemory product into us for a peek. Their Radeon X1300 HyperMemory 2 does the same local-plus-system memory dance, but it moves the HyperMemory game on quite significantly.
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