Apple iMac (27-inch, Late 2009, Core i5 and i7)
Model identifier iMac11,1 All-in-one, from 2009 40 hardware reports
Upgradable
Yes. 4 slots, up to 16 GB seen working.
It takes DDR3-1066 laptop-size sticks (SO-DIMM).
- Slots
- 4 SO-DIMM slots
- Type
- DDR3-1066 204-pin SO-DIMM
- Most seen working
- 16 GB in two or more machines; one machine runs 32 GB
- Firmware says
- 16 GB maximum
- How sure
- 24 of 24 reports show this layout
See 4 GB DDR3-1066 SO-DIMM on AmazonOpens an Amazon search for this exact spec.
Worked out from 24 hardware reports of this desktop, with Apple's memory specifications for which Macs have sockets. Sources and method. Updated 10 Nov 2026.
4 laptop-size slots
Illustration Questions
Can I upgrade the RAM in the Apple iMac (27-inch, Late 2009, Core i5 and i7)?
Yes. 4 slots, up to 16 GB seen working. It takes DDR3-1066 laptop-size sticks (SO-DIMM).
What type of RAM does the Apple iMac (27-inch, Late 2009, Core i5 and i7) use?
DDR3-1066 laptop-size sticks (SO-DIMM, 204-pin).
How much RAM can the Apple iMac (27-inch, Late 2009, Core i5 and i7) take?
Machines in the reports run up to 16 GB, and one runs 32 GB. That matches the 16 GB maximum the firmware reports.
Is this my desktop?
On the Mac, choose Apple menu > About This Mac > System Report. The Model Identifier should read iMac11,1.
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