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21.5-inch iMac (Late 2013) Review: Iris Pro Driving an Accurate Display
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Upgrade RAM Apple iMac 21.5 slim A1418
A-Tech 16GB Kit (2x8GB) RAM for Apple MacBook Pro (Mid 2012), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015), Mac Mini (Late 2012) | DDR3 1600MHz PC3-12800 SODIMM 204-Pin Memory Upgrade at Amazon.com
How to upgrade RAM iMac late 2013 21.5inch - break & fix MOVIE - YouTube