Amazon.com: Original Graphics Video Card for Apple iMac 2011 Core i5 2.7 A1312 MC813LL/A MC813 27 Inch Desktop PC Computer AMD Radeon HD 6770M HD6770M GDDR5 512MB 109-C29557-00 Replacement Parts : Electronics
Cracking Open the 27" Apple iMac (2011) | TechRepublic
2GB Graphics Video Card Replacement for Apple iMac Mid-2011 27 Inch A1312 Core i7 3.4 MD063LL/A MD063 Desktop PC Computer, ATI Radeon HD 6970 GDDR5 2 GB, New GPU Upgrade Repair Parts : Electronics - Amazon.com