MojoKid writes "Apple is pitching Mac OS X 10.8 (Mountain Lion) as the cat's meow with over 200 new features "that add up to an amazing Mac experience," but that only applies if you're rocking a compatible system. Some older Mac models, including ones that are 64-bit capable, aren't invited to the Mountain Lion party, and it's likely because of the GPU. It's being reported (unofficially) that an updated graphics architecture intended to smooth out performance in OS X's graphics subsystem is the underlying issue. It's no coincidence, then, that the unsupported GPUs happen to be ones that were fairly common back before 64-bit support became mainstream."
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