21.5" Inch iMac Late 2013 A1418 RAM PCIe NVMe SSD Hard Drive Upgrade PSU Logicboard Replacement - YouTube
Memory Upgrades for iMac 21.5-Inch 2012 - Late 2013
2015 A1418 can I upgrade the RAM? - iMac Intel 21.5" Retina 4K Display (2015) - iFixit
HOW I UPGRADED MY iMAC 21.5in Late 2013 MODEL (SSD & RAM UPGRADE) - YouTube
How to Upgrade iMac RAM: 2012-2022: EveryMac.com
OWC 16GB (2x8GB) ram Upgrade PC3-12800 DDR3L 1600MHz sodimm 204 Pin CL11 Memory Upgrade Kit Compatible with Late iMac, Mac Mini, and MacBook Pro Computer at Amazon.com
Apple Mac Memory Ram Upgrades Dublin
Apple iMac 21.5" A1418 Intel Core i5-4640 / 8GB Ram Logic Board P/N 820-4668-A for sale online | eBay