5 Things to Know About the 27-Inch iMac (2015) RAM Upgrade

RAM is user-accessible The 27-inch iMac has a RAM access door on the back, so you do not need to remove the screen to upgrade memory.

Official maximum is 32GB Apple officially supports up to 32GB using four 8GB 1867MHz DDR3 SO-DIMMs.

64GB may work with third-party modules Some users have successfully installed 64GB using third-party memory, though it is not officially supported.

Use matching modules for best stability Mixing different capacities or speeds can cause issues, so stick with identical modules.

Worth trying 64GB if you need more headroom If you run memory-intensive tasks like video editing or virtual machines, the unofficial 64GB upgrade is worth attempting.