Baseline Vista offerings will require 512MB of DRAM just to install, with a 1GB recommendation -- but is there more to this story? Integrated graphics from ATI, Intel, and NVIDIA all use shared memory architectures. This means that even though the graphics core is on the motherboard Northbridge, the graphics controller accesses memory from the system main memory. Low end, PCIe 3D accelerations from ATI, and NVIDIA also use shared memory support, using in excess of 256MB of system DRAM in exchange for a dirt cheap graphics accelerator. On these systems the Vista recommendation for 512MB is not acceptable as a significant amount of main memory is consumed by the graphics accelerators.

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