IMac12,1 Late 2011: MC978LL/A (3.1 GHz Core i3). iMac12,1 Mid 2011: MC812LL/A (2.8 GHz Core i7). iMac12,1 Mid 2011: MC812LL/A (2.7 GHz Core i7). iMac12,1 Mid 2011: MC309LL/A (2.5 GHz Core i5). iMac 21.5" A1311.
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