hardware - Installing 2 x 16Gb and 2 x 32Gb on an iMac 27" - Ask Different
iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
OWC 8 GB (2 X 4GB) ram PC8500 DDR3 1066MHz sodimm 204-pin Memory Upgrade Kit, (OWC8566DDR3S8GP), Compatible with MacBook Pro, MacBook, Mac Mini and iMac at Amazon.com
OWC 16GB (2 x 8GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with 27" iMac w/Retina 5K (Mid 2017), Mac Mini (Late 2018), and Compatible PCs | Walmart Canada
Crucial vs Samsung vs OWC memory for iMac 2020 | MacRumors Forums
OWC vs Crucial Memory | MacRumors Forums
iMac RAM Upgrade Worth It? - YouTube
Mac RAM Upgrade, Best iMac Memory Upgrade – Best Reviews