iMac 27' (mid 2011) fix for AMD Radeon HD 6970M no video problem - YouTube
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Apple iMac 27" Late 2009 i7-860 2.8GHz 16 GB RAM, 240GB SSD, Radeon HD 6970M 1GB | eBay
AMD Radeon HD 6770M Mac Edition Specs | TechPowerUp GPU Database
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