Apple Initiates Video Card Replacement Program for Radeon HD 6970M Equipped Mid-2011 27” iMacs
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Amazon.com: Valley Of The Sun 2 GB Graphics Video Card GPU Upgrade Replacement for Apple iMac Mid-2011 A1312 27 Inch Core i7 3.4 i5 3.1 Desktop Computer, New AMD Radeon HD 6970M
Original Ati HD 6970M 5750m 4850 4670 Graphics Card Video Card 1GB 2GB 109-C29657-10
AMD launches a dual-GPU, 350W monster card | Ars Technica