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iMac Intel 20" EMC 2133 and 2210 Video Card Replacement - iFixit Repair Guide
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
Late 2009 iMac 27" Video Card Repair [4850 Bake] - YouTube
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SOLVED: What GPU's are compatible with iMac 27" 2011? - iMac Intel 27" EMC 2429 - iFixit
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