How to Upgrade Memory in a 27-inch iMac (Late 2012-2013) iMac13,2 and iMac14,2 - YouTube
iMac 27-Inch "Core i7" 3.5 Late 2013 Max RAM is higher than 32gb | MacRumors Forums
21.5" iMac Has No User-Upgradable RAM; 27" Has Four Accessible RAM Slots - MacRumors
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2012 2013 2014 Apple Imac 5k 27 Inch Memory Ram 4gb 8gb 16gb 32gb Ddr3 1600 - Rams - AliExpress