iMac 2009 to 2011 (A1311/A1312) Upgrade Guide – MacintoshMen
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 Repair Parts
2011 iMac 27″ K1100M Graphics Card Swap And Install Catalina – TuXxX Blog
Upgrading an iMac GPU for METAL Support! Late 2009 – Mid 2011 Models - YouTube
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