iMac Intel 27" EMC 2374, AMD Radeon HD 4850 Video Card Removal & Repair - iFixit Repair Guide
Need to repair this iMac 27" 2011, Please any suggestions? GPU Temperature is not even 50 C : r/mac
iMac 27" mid-2011 GPU upgrade
2011 iMac GPU Upgrade Now with Brightness and Boot menu - Absolutely Worth It! - YouTube
2GB Graphics Video Card HD6970M Replacement, for iMac Mid-2011 27 Inch A1312 Desktop PC Computer Core i5 MAC814LL/A MC814, AMD Mobility Radeon HD 6970M GPU Upgrade MXM Board Repair Parts
iMac 2009 to 2011 (A1311/A1312) Upgrade Guide – MacintoshMen