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Apple Initiates Video Card Replacement Program for Radeon HD 6970M Equipped Mid-2011 27” iMacs
Amazon.com: New HD 6970M 2GB Graphics Card Replacement for iMac Mid-2011 27" All-in-One Desktop PC Core i7 3.4 MD063LL/A MD063, AMD Radeon HD6970M HD6970 GPU Upgrade MXM Video Board Repair Parts :
Brand New Hd6970 Hd6970m 2gb Video Card For Apple Imac 27" A1312 2011 Radeon Hd 6970m 216-0811000 Graphic Card 109-c29657-10 - Laptop Repair Components - AliExpress
Amazon.com: New HD 6970M 2GB Graphics Card Replacement for iMac Mid-2011 27" All-in-One Desktop PC Core i7 3.4 MD063LL/A MD063, AMD Radeon HD6970M HD6970 GPU Upgrade MXM Video Board Repair Parts :
AMD Radeon HD 6970M Mac Edition Specs | TechPowerUp GPU Database