Amazon.com: Valley Of The Sun Graphics Video Card GPU Replacement for Apple iMac Mid-2010 A1311 Core i3 3.06 MC508LL/A MC508 21.5 Inch Desktop Computer, ATI Radeon HD 4670 GDDR3 256MB, MXM VGA
Original Ati HD 6970M 5750m 4850 4670 Graphics Card Video Card 1GB 2GB 109-C29657-10 For Apple iMac 27" A1312 GPU 2009 2010 2011 - AliExpress
For iMac 27" A1312 Mid 2009 2010 2011 6970m 1GB 2GB 109-C29657-10 Upgrade For Nvidia GTX 780M DDR5 4GB MXM TYPE-B VIDEO GPU CARD - AliExpress
Amazon.com: 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 :
Nvidia K1100M upgrade on the Mid-2010 iMac 21.5' - YouTube
2010 iMac GPU Upgrade to NVIDIA GTX 765M - YouTube
Intel iMac 27" ATI Radeon HD 5750 1GB Video Card DIY Parts replacement Video Cards
iMac 2009 to 2011 (A1311/A1312) Upgrade Guide – MacintoshMen
Amazon.com: Valley Of The Sun Genuine Graphics Video Card Replacement for Apple iMac Mid-2010 Core i5 A1312 27-Inch MC511LL/A MC511 Desktop PC, ATI Mobility Radeon HD 5750 GDDR5 1GB MXM Board :
Graphics Card, Radeon HD - iMac 21.5″ A1311 (Mid 2010)