iMac 27-inch (2015)

Can the RAM be upgraded in the iMac 27-inch (2015)?

Yes. The iMac 27-inch (2015) has a user-accessible RAM compartment behind a door on the back. It supports up to 32GB (4x8GB) of 1867MHz DDR3 SO-DIMMs, though some users have successfully installed 64GB (4x16GB) with third-party modules.

What is the maximum RAM capacity?

Officially, Apple states a maximum of 32GB, but the iMac 27-inch (2015) can support up to 64GB using four 16GB 1867MHz DDR3 SO-DIMMs.

Can the internal storage be upgraded?

Yes, but it requires disassembling the display. The iMac 27-inch (2015) uses a proprietary PCIe-based SSD connector or a 3.5-inch SATA III hard drive. The SSD can be replaced with a compatible NVMe drive using an adapter, or the HDD can be swapped for a 2.5-inch SATA SSD.

Is the battery replaceable?

The iMac 27-inch (2015) does not have a user-replaceable battery. It uses a built-in coin cell battery (CR2032) for the PRAM/SMC, which can be replaced by opening the computer.

Can the CPU or GPU be upgraded?

The CPU is socketed (LGA 1150) and can be upgraded to a compatible Intel Core i5 or i7 processor, but it requires full disassembly. The GPU is soldered to the logic board and cannot be upgraded.

What other components are upgradeable?

The Wi-Fi/Bluetooth card is replaceable with a compatible model. The display panel and fans can also be swapped, but these require significant disassembly.

Can the optical drive be upgraded?

No. The iMac 27-inch (2015) does not include an optical drive. If you need one, you must use an external USB drive.