Amazon.com: Valley Of The Sun New 2GB Graphics Video Card Upgrade for Apple iMac Mid-2011 27 Inch Core i5 MC814LL/A MC814 A1312 Desktop All-in-One PC, AMD Mobility Radeon HD 6970M Replacement :
iMac Intel 21.5" EMC 2428 Radeon HD 6750M Graphics Card
For iMac 27" A1312 Mid 2009 2010 2011 upgrade NVIDIA GTX 880M 8GB Video Card | eBay
For iMac 27" A1312 Mid 2009 2010 2011 upgrade NVIDIA GTX 780M 4GB Video Card | eBay
Amazon.com: Valley Of The Sun New 2GB Graphics Video Card Upgrade for Apple iMac Mid-2011 27 Inch Core i5 MC814LL/A MC814 A1312 Desktop All-in-One PC, AMD Mobility Radeon HD 6970M Replacement :
Original Ati HD 6970M 5750m 4850 4670 Graphics Card Video Card 1GB 2GB 109-C29657-10 For Apple iMac 27" A1312 GPU 2009 2010 2011 - AliExpress
Amazon.com: 2GB Graphics Card GPU Upgrade Replacement for iMac 27 Inch Mid- 2011 A1312 Desktop Computer Core i5 3.1 MC814LL/A MC814, AMD Radeon HD 6970M GDDR5 2 GB MXM Video Board Repair Parts :
mid-2011 iMac 27 graphics issue: Mac Talk Forum: Digital Photography Review
Apple 730-0628-A iMac 27" A1312 Mid 2011 Graphics Card Heatsink with Sensor | Heatsinks | Team Spares
Amazon.com: Valley Of The Sun New 2GB Graphics Video Card Upgrade for Apple iMac Mid-2011 27 Inch Core i5 MC814LL/A MC814 A1312 Desktop All-in-One PC, AMD Mobility Radeon HD 6970M Replacement :