OWC Tears Down iMac Retina 4K, Confirms Memory Is Soldered
Upgrade RAM on Apple Retina iMac 5K (Late 2015) / How To install memory - YouTube
iMac RAM Upgrade 8GB-32GB (Late 2015) - YouTube
2017 21.5-inch 4K iMac memory upgrade kit includes 32GB of RAM, tools to take it apart | AppleInsider
Apple iMac 27" 2015 - i5 3.3GHz - 16GB RAM - 2TB HDD - Model Number MK782LL/A - Grade B Used - Walmart.com
Apple iMac 5K Retina 27" Desktop - 4.0GHz Quad-Core i7 - 32GB RAM - 1T – The Refurbished Apple Store
A-Tech 32GB (4x8GB) RAM for Apple iMac Late 2015 27 inch Retina 5K | DDR3L 1866MHz / 1867MHz PC3L-14900 1.35V 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
iMac 21.5" A1418 Late 2015 Logic Board 2.8 GHz Core i5 16GB Ram || NO - Part Haven
Logic Board 3.1 GHz i5 16GB Ram iMac Retina 4K 21.5" Late 2015 A1418 W - Part Haven
OWC 8GB (2 x 4GB) PC12800 DDR3L 1600MHz SO-DIMMs Memory Compatible with 2011-2015 iMac, 2011-12 Mac Mini, and 2011-2012 MacBook Pro (Non-Retina Display) Models (OWC1600DDR3S08S) at Amazon.com
iMac (Retina 5K, 27-inch, Late 2015) - Technical Specifications