Apple said that would run happily on a late 2009 or later MacBook or iMac, or a 2010 or later MacBook Air, MacBook Pro, Mac mini or Mac Pro. If you Mac is supported read: How to update to Big Sur. Using matched 2 GB modules, the iMac accesses only 3 GB of 4 GB installed. IMac 6,1 Late 2006. 2: 200-pin PC2-5300 DDR2 (667 MHz) SO-DIMM. Yes: Using matched 2 GB modules, the iMac accesses only 3 GB of 4 GB installed. IMac 7,1 Mid 2007. 2: 200-pin PC2-5300 DDR2 (667 MHz) SO-DIMM. Yes: Use matched 2 GB modules. IMac 8,1 Early 2008: 2. The iMac is Apple's line of all-in-one desktop computers. Replace the hard drive in an iMac Intel 27' EMC 2429. IMac Intel 27' EMC 2309 and 2374 Hard Drive Replacement iMac Intel 27' EMC 2309 and 2374 Hard Drive replacement. Easily check which versions of mac OS, iOS, iPadOS, or watchOS are compatible with your Mac model or iDevice. Guide includes OS X 10.8.x to macOS 11.0.x.
If you're not sure which iMac you have, you can identify your iMac and then select it from the list below.
27-inch
24-inch
21.5-inch
20-inch
17-inch
* Memory is not removable by users on iMac (21.5-inch, Late 2012), iMac (21.5-inch, Late 2013), iMac (21.5-inch, Mid 2014), iMac (21.5-inch, 2017), iMac (Retina 4K, 21.5-inch, 2017), and iMac (Retina 4K, 21.5-inch, 2019). If the memory in one of these computers needs repair service, contact an Apple Retail Store or Apple Authorized Service Provider. If you’d like to upgrade the memory in one of these models, an Apple Authorized Service Provider can help. Before you schedule an appointment, confirm that the specific Apple Authorized Service Provider offers memory upgrade services.
Memory in iMac (21.5-inch, Late 2015), and iMac (Retina 4K, 21.5-inch, Late 2015) is not upgradeable.
Get memory specifications for iMac (Retina 5K, 27-inch, 2020), then learn how to install memory in this model.
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB (2 x 4GB DIMMs) |
Maximum memory | 128GB (4 x 32GB DIMMs) |
For optimal memory performance, DIMMs should be the same capacity, speed, and vendor. Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
If you have mixed capacity DIMMs, see the install memory section for installation recommendations.
Get memory specifications for iMac (Retina 5K, 27-inch, 2019), then learn how to install memory in this model.
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB (2 x 4GB DIMMs) |
Maximum memory | 64GB (4 x 16GB DIMMs) |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
Get memory specifications for iMac (Retina 5K, 27-inch, 2017), then learn how to install memory in this model.
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB (2 x 4GB DIMMs) |
Maximum memory | 64GB (4 x 16GB DIMMs) |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
Get memory specifications for iMac (Retina 5K, 27-inch, Late 2015), then learn how to install memory in this model.
This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB |
Maximum memory | 32GB |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
Get memory specifications for the following iMac models, then learn how to install memory in them:
These iMac models feature Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:
Number of memory slots | 4 |
Base memory | 8GB |
Maximum memory | 32GB |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After you shut down your iMac and give it time to cool, follow these steps:
Your iMac performs a memory initialization procedure when you first turn it on after upgrading memory or rearranging DIMMs. This process can take 30 seconds or more, and the display of your iMac remains dark until it's finished. Make sure to let the memory initialization complete.
Get memory specifications for the following iMac models, then learn how to install memory in them:
Number of memory slots | 4 |
Base memory | 4GB (but is configured to order) |
Maximum memory | 16GB For iMac (Late 2009), you can use 2GB or 4GB RAM SO-DIMMs of 1066MHz DDR3 SDRAM in each slot. For iMac (Mid 2010) and iMac (Mid 2011), use 2GB or 4GB RAM SO-DIMMs of 1333MHz DDR3 SDRAM in each slot. |
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
iMac (Mid 2011) | iMac (Mid 2010) | iMac (Late 2009) |
PC3-10600 | PC3-10600 | PC3-8500 |
Unbuffered | Unbuffered | Unbuffered |
Nonparity | Nonparity | Nonparity |
204-pin | 204-pin | 204-pin |
1333MHz DDR3 SDRAM | 1333MHz DDR3 SDRAM | 1066MHz DDR3 SDRAM |
i5 and i7 Quad Core iMac computers come with both top memory slots populated. These computers will not start up if only a single DIMM is installed in any bottom slot; these computers should operate normally with a single DIMM installed in any top slot.
Core Duo iMac computers should operate normally with a single DIMM installed in any slot, top or bottom. ('Top' and 'bottom' slots refer to the orientation of the slots in the pictures below. 'Top' refers to the slots closest to the display; 'bottom' refers to the slots closest to the stand.)
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After you shut down your iMac and give it time to cool, follow these steps:
Get memory specifications for the following iMac models, then learn how to install memory in them:
These iMac computers have two side-by-side Synchronous Dynamic Random-Access Memory (SDRAM) slots in the bottom of the computer.
The maximum amount of random-access memory (RAM) you can install in each computer is:
Computer | Memory Type | Maximum Memory |
iMac (Mid 2007) | DDR2 | 4GB (2x2GB) |
iMac (Early 2008) | DDR2 | 4GB (2x2GB) |
iMac (Early 2009) | DDR3 | 8GB (2x4GB) |
You can use a 1GB or 2GB RAM module in each slot for iMac (Mid 2007) and iMac (Early 2008). Use 1GB, 2GB, or 4GB modules in each slot for the iMac (Early 2009).
Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:
iMac (Mid 2007) | iMac (Early 2008) | iMac (Early 2009) |
PC2-5300 | PC2-6400 | PC3-8500 |
Unbuffered | Unbuffered | Unbuffered |
Nonparity | Nonparity | Nonparity |
200-pin | 200-pin | 204-pin |
667MHz DDR2 SDRAM | 800MHz DDR2 SDRAM | 1066MHz DDR3 SDRAM |
DIMMs with any of the following features aren't supported:
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After your iMac cools down, follow these steps:
Get memory specifications for the following iMac models, then learn how to install memory in them:
Number of memory slots | 2 | ||
Base memory | 1GB | Two 512MB DIMMs; one in each of the memory slots | iMac (Late 2006) |
512MB | One DDR2 SDRAM installed into the top slot | iMac (17-inch Late 2006 CD) | |
512MB | Two 256MB DIMMs; one in each of the memory slots | iMac (Mid 2006) | |
512MB | One DDR2 SDRAM installed into the top slot | iMac (Early 2006) | |
Maximum memory | 4GB | 2 GB SO-DIMM in each of the two slots* | iMac (Late 2006) |
2GB | 1GB SO-DIMM in each of the two slots | iMac (17-inch Late 2006 CD) iMac (Early 2006) | |
Memory card specifications | Compatible: - Small Outline Dual Inline Memory Module (DDR SO-DIMM) format - PC2-5300 - Nonparity - 200-pin - 667 MHz - DDR3 SDRAM | Not compatible: - Registers or buffers - PLLs - ECC - Parity - EDO RAM |
For best performance, fill both memory slots, installing an equal memory module in each slot.
*iMac (Late 2006) uses a maximum of 3 GB of RAM.
The internal components of your iMac can be warm. If you've been using your iMac, wait ten minutes after shutting it down to let the internal components cool.
After you shut down your iMac and give it time to cool, follow these steps:
After you shut down your iMac and give it time to cool, follow these steps:
iMac models introduced before 2017 might make a warning sound when you start up after installing or replacing memory:
If you hear these tones, confirm that the memory you installed is compatible with your iMac and that it's installed correctly by reseating the memory. If your Mac continues to make the tone, contact Apple Support.
After you install memory, you should confirm that your iMac recognizes the new RAM by choosing Apple () menu > About This Mac.
The window that appears lists the total memory, including the amount of memory that originally came with the computer plus the newly added memory. If all the memory in the iMac has been replaced, it lists the new total of all installed RAM.
For detailed information about the memory installed in your iMac, click System Report. Then choose Memory under the Hardware section in the left side of System Information.
If your computer doesn't recognize the memory or doesn't start up correctly, confirm that the RAM you installed is compatible with your iMac and that it's installed correctly by reseating the memory. If you continue to have issues with the memory in your iMac, contact Apple Support.