661-5969 Apple Radeon HD 6970M 2GB Video Graphics Card for iMac (27-inch Mid 2011)
Amazon.com: GDDR5 2GB Graphics Video Card Radeon HD 6970M for Apple iMac Mid-2011 27 Inch Core i5 i7 All-in-One Desktop PC Computer, AMD Radeon HD6970M HD6970 MXM Board GPU Upgrade Repair Parts :
NEW Apple iMac 27" A1312 mid 2011 AMD Radeon HD 6970M 2GB DDR5 VGA Video Card | eBay
NEW Apple iMac 27" A1312 mid 2011 AMD HD 6970M 2GB DDR5 GPU Video Card HD6970 | eBay