The iMac 27-inch 2015 can hold more RAM than Apple advertises

Apple officially says the 27-inch iMac from 2015 tops out at 32 GB of RAM, but the machine can actually take twice that. With four 16 GB 1867 MHz DDR3 SO-DIMMs, the iMac runs happily at 64 GB. One of those cases where the real ceiling is well above the official number — a nice bonus if you’re buying secondhand.