Previous models had soldered memory modules, but the new iMac's memory sits in two removable SO-DIMM slots.
iFixit voided the warranty on Apple's $1,299 mid-range 3.0GHz stock option, which includes 8GB of 2400MHz DDR4 memory, a Radeon Pro 555 graphics card with 2GB of VRAM, and a 1TB 5400-RPM hard drive.
After slicing through the adhesive that secures the 4K display to the iMac's housing and removing the power supply, hard drive, and fan, iFixit discovered that the memory modules were not soldered onto the logic board like previous models, but instead sit in two removable SO-DIMM slots.
"It may not be as accessible as the (dead simple) RAM hatch found in the 27" iMacs—but still, this is a major win for upgradability over all the 21.5" iMacs with soldered RAM that we've encountered in recent years," the outfit said.
After detaching the heatsink and removing the warranty voiding stickers on the backside of the logic board, iFixit found that the Intel SR32W Core i5-7400 Kaby Lake processor sits in a standard LGA 1151 CPU socket, making it possible to replace or upgrade the CPU without a reflow station.