iMac Pro Teardown Highlights Modular RAM, CPU and SSD Along With Redesigned Internals - MacRumors
How to UPGRADE RAM in the (Mid 2017) 5K iMac & save $$$! - YouTube
Adamanta 16GB (2x8GB) Memory Upgrade for 2020 Apple iMac 27" w/Retina 5K Display, 2019 Apple iMac 27" w/Retina 5K Display, 2018 Apple Mac Mini DDR4 2666Mhz PC4-21300 SODIMM 1Rx8 CL19 1.2v DRAM
64GB (2x32GB) NEMIX RAM Memory for 2019 Apple iMac 27 inch Retina 5K (iMac19,1 A2115), 2018 Apple Mac Mini (Macmini8,1 A1993) - Newegg.com