2012 21.5-Inch Apple iMac Review: Slim, Sleek, And Stylish, But Far From Shallow | TechCrunch
hardware - Can I add different size RAMs to iMac 5K? - Ask Different
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
It's Dead Easy to Swap the RAM on a 27” iMac (Late 2012) – How To
How to Upgrade/Install Memory in a 21.5-inch iMac (Late 2012– Mid 2014) iMac14,1 iMac14,3 - YouTube