For iMac 21.5" A1311 Mid/Late 2009 2010 2011 NVIDIA K1100M 2GB Video Card | eBay
Amazon.com: 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 : Electronics
Upgrading an iMac GPU for METAL Support! Late 2009 – Mid 2011 Models - YouTube
2011 iMac 27″ GPU failure Fix/Upgrade – JCYCLE
2011 iMac Graphics Card Upgrade | How to | Mac Expert Guide
For iMac 21.5" A1311 Mid/Late 2011 AMD upgrade Nvidia K1100m 2GB Video Card | eBay
2010 iMac GPU Upgrade to NVIDIA GTX 765M - YouTube
Amazon.com: 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
Burn the VGA and Fix your iMac - Don't Pay Shitty Problems!!! - YouTube