Amazon.com: 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 HD6970M 2GB MXM Board
Apple opens graphics card replacement program for some mid-2011 iMacs - 9to5Mac
A1312 iMac GPU Replacement - YouTube
1.5.8 with iMac Mid 2011 27" loses the GPU Heatsink sensor · Issue #406 · crystalidea/macs-fan-control · GitHub
Late 2009 iMac 27" Video Card Repair — 4850 — 2nd Bake - YouTube
Amazon.com: Valley Of The Sun 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 Repair Parts :
Apple iMac 27" Mid 2011 Video Card - ATI Radeon 6970 with 1GB GDDR5 me - Part Haven
iMac Intel 27" EMC 2429 Radeon HD 6770M Graphics Card