Memory RAM 1x 4GB Apple iMac Late 2012 DDR3 1600MHz SO-DIMM | E-OWC1600DDR3S4GB | APPLE \ MEMORY FOR APPLE \ OWC \ APPLE IMAC \ iMac Late 2012 \ iMac 27'' (Late
OWC Turnkey Upgrade Program for 2017 iMac Pro Memory Upgrade
iMac Pro teardown video has good and bad upgrade news - SlashGear