Tarjeta gráfica Original Ati HD 6970M, 5750m, 4850, 4670, 1GB, 2GB, 109-C29657-10, para Apple iMac de 27 pulgadas, A1312, GPU 2009, 2010, 2011 - AliExpress
Late 2009 iMac 27" Video Card Repair — 4850 — 2nd Bake - YouTube
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Amazon.com: Genuine Graphics Video Card GPU Replacement for Apple iMac Core 2 Duo 2.0 20-Inch A1224 MA876LL Desktop Computer, ATI Mobility Radeon HD 2400 XT GDDR3 128MB, MXM GPU VGA Board Repair
Apple iMac Graphics Card Repair, Replace Chipset (not BGA Reballing or Reflow) | eBay
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 :