Original Graphics Video Card GPU Upgrade Replacement for Apple iMac 21.5 Inch Late 2011 Core i3 3.1 All-in-One Desktop PC MC978LL/A, AMD ATI Mobility Radeon HD 6750M, MXM VGA Board Repair Parts : Electronics - Amazon.com
New 2GB Graphics Video Card GPU Upgrade Replacement, for iMac 27 Inch Mid 2011 All-in-One Desktop Computer A1312 Core i7 3.4 MD063LL/A, AMD Radeon HD 6970M GDDR5, MXM VGA Board Repair Parts-
For iMac 27" A1312 Mid 2009 2010 2011 upgrade NVIDIA K4100M 4GB GPU Video Card | eBay
Original HD6970M HD6970 2GB VGA Video Graphic Card for Apple iMac 27" mid 2011 A1312 A1311 661 5969 109 C29657 10|Add On Cards| - AliExpress
SOLVED: What GPU's are compatible with iMac 27" 2011? - iMac Intel 27" EMC 2429 - iFixit
SOLVED: What GPU's are compatible with iMac 27" 2011? - iMac Intel 27" EMC 2429 - iFixit
2GB Graphics Video Card Improve for Apple iMac Mid-2011 27 Inch Core i5 MC814LL/A MC814 A1312 Desktop All-in-One PC, AMD Mobility Radeon HD 6970M Alternative Restore Elements - Top Motherboards
For iMac 21.5" A1311 Mid/Late 2011 6770 AMD upgrade Nvidia K610m 1GB Video Card | eBay