Several modern CPU parts such as 3rd Gen (and later) Intel Core Processors (e.g. Ivy Bridge and Haswell) and all AMD APUs (e.g. Llano and Trinity), have an on-die integrated GPU accelerator which shares the same physical RAM with the CPU. On such parts creating copies of data from CPU memory for GPU access and (vice-versa) is mostly unnecessary. The same is applicable for the C++ AMP CPU fallback WARP accelerator.