There's ~17 steps just to get to [guide|6272|the card] '''- not a beginners DIY project.'''..
Officially, Apple provides some models with upgraded video options at the time of purchase, but''' the video is not intended to be upgraded by a third-party'''. However, based on disassembly photos and a variety of teardowns, it appears that '''some models have the video mounted on its own card and it is theoretically upgradable in these systems. ''' '' Possibility MIGHT BE: 512 MB Radeon HD 5670...''
If video expansion is a top priority,''' you would likely be better served by selling your current unit and switching to a Mac Pro.'''
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