Apple Mac Studio: Hardware im Vergleich zum Mac Pro und iMac | STERN.de
Amazon.com: Original Graphics Video Card for Apple iMac Core i7 2.8 27-Inch Late 2009 A1412 MC507LL/A MC507 Desktop Computer, AMD ATI Mobility Radeon HD 4850 GDDR3 512MB 109-B91157-00, GPU Upgrade Replacement : Electronics
Grafikkarte ATI Radeon HD 4670M iMac A1311 A1312 2011 109-B80357-00 no power VGA | eBay
iFixit zerlegt iMac, Grafikkarte austauschbar | Mac Life