How to Upgrade/Install Memory in a 21.5-inch iMac (Late 2012– Mid 2014) iMac14,1 iMac14,3 - YouTube
How to upgrade RAM iMac late 2013 21.5inch - break & fix MOVIE - YouTube
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iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
16GB -2x8GB Memory Ram Upgrade 21.5" Apple iMac-14.1 Core i5 2.7GHz Late 2013 | eBay
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Install memory in an iMac - Apple Support
How To Upgrade RAM in a Mac | Macworld
SSD Upgrades for Apple iMac 27-Inch Late 2013 - 2019
Apple iMac 21.5-inch and 27-inch (Late 2013) reviews | Macworld
NEMIX RAM 16GB Kit (2x8GB Upgrade) DDR3-1600 SODIMM PC3-12800 for Apple MacBook Pro Mid 2012 / iMac Late 2012 / iMac 2013, Late 2014, Mid 2015, Mac Mini Late 2012 at Amazon.com