iMac: Memory specifications and upgrades

Summary

Learn about the types of random access memory (RAM) and video memory (VRAM) used in iMac computers. For specific instructions on installing memory, refer to the linked documents.

Products Affected

iMac, iMac (21.5-inch, Mid 2011), iMac (27-inch, Mid 2011)

Learn how to identify which iMac model you have, then refer to this table.

iMac Model	Max. DRAM	User Installable Slot	AASP Installable Slot	Video/ VRAM	Notes
iMac (27-inch, Mid 2011)	16 GB	PC3-10600 (1333) DDR3 204-pin SO-DIMM		512 MB GDDR5 SDRAM and 1 GB GDDR5 SDRAM	2
iMac (21.5-inch, Mid 2011)	16 GB	PC3-10600 (1333) DDR3 204-pin SO-DIMM		512 MB GDDR5 SDRAM	2
iMac (27-inch, Mid 2010)	16 GB	PC3-10600 (1333) DDR3 204-pin SO-DIMM		512 MB GDDR3 SDRAM and 1 GB GDDR5 SDRAM	2
iMac (21.5-inch, Mid 2010)	16 GB	PC3-10600 (1333) DDR3 204-pin SO-DIMM		256 MB up to 512 MB GDDR3 SDRAM	2
iMac (Late 2009)	16 GB	PC3-8500 (1066) DDR3 204-pin SO-DIMM		256 up to 512 MB GDDR3 SDRAM	2
iMac (Mid 2009)	4 GB	PC3-8500 (1066) DDR3 204-pin SO-DIMM		256 up to 512 MB GDDR3 SDRAM
iMac (Early 2009)	8 GB	PC3-8500 (1066) DDR3 204-pin SO-DIMM		256 up to 512 MB GDDR3 SDRAM
iMac (Early 2008)	4 GB	PC2-6400 (800) DDR2 200-pin SO-DIMM		128 or 256 MB GDDR3 SDRAM
iMac (Mid 2007)	4 GB	PC2-5300 (667) DDR2 200-pin SO-DIMM		128 or 256 MB GDDR3 SDRAM
iMac (Late 2006)	4 GB	PC2-5300 (667) DDR2 200-pin SO-DIMM		128 MB GDDR3 SDRAM	1
iMac (Mid 2006) and iMac (17-inch Late 2006 CD)	2 GB	PC2-5300 (667) DDR2 200-pin SO-DIMM		64 MB GDDR3 SDRAM
iMac (Early 2006)	2 GB	PC2-5300 (667) DDR2 200-pin SO-DIMM		128 MB GDDR3 SDRAM

Notes:

All iMac models have multiple memory slots. See articles for each individual iMac model to learn how much memory can be installed in each slot.

Although the iMac (Late 2006) computers will accept up to a 2 GB SO-DIMM in each of the two memory slots, the iMac will only support 3 GB total memory.
The iMac (Late 2009), iMac (Mid 2010) and iMac (Mid 2011) have four SDRAM slots, each of which can accept a 2 GB or 4 GB SO-DIMM.