How to upgrade iMac (2020) RAM and save up to $ 2000

Last week Apple released what could be a swan song for the current design of the 27-inch iMac. With the Apple Silicon-based Mac on the horizon, it’s possible that we’ve seen the last part of the current iMac’s design, and with it the end of user-accessible memory that makes it easy to upgrade iMac (2020) RAM.

The current 5K iMac design is unique, as it is the only Mac machine Apple sells outside of the $ 6000 Mac Pro that features user-enhanced memory. Thanks to a special door above the power socket behind the 27-inch iMac, users can gain access to the machine’s four SO-DIMM slots to upgrade the RAM.

The iMac Pro also does not offer users such a cost-saving luxury, which makes the 5K iMac a value-packed machine. And in 2020 iMac is now officially supporting 128GB of RAM in a build-to-order configuration, users can buy third-party RAM and save a lot of money, up to $ 2000. See our hands-on step-by-step tutorial for details, and be sure to subscribe to 9to5Mac on YouTube for more iMod content.

For the first time, Apple is allowing iMac users, even those who purchase the base model $ 1,799 configuration, to massively upgrade to 128GB of RAM. [side note, last year’s 5K iMac could support 128GB as well, but unofficially]. As has long been the case, however, Apple charges a great deal of money for memory upgrades, and the iMac (2020) is no exception to this long-term trend.

By default all iMac configurations come with at least 8GB of DDR4 2666MHz memory. The 8-inch memory configuration comes via a 4GB SO-DIMM module installed in two of the four SO-DIMM slots placed on the rear of the 27-inch iMac chassis.

How Much Can you Save?

Here is a comparison of the Apple charges that you would normally pay through a third party like a memory module. Third-party prices are rounded up and estimates. Keep in mind that memory prices may be slightly lower here and there. As you can see, users use the 128GB configuration stand to save some serious coins, but even if you opt for an upgrade to 32 or 64GB, you still stand to save hundreds of dollars.

128GB RAM for 5K iMac for just $ 600
price Apple price Third party price Savings
16 GB $ 200 $ 70 $ 130
32GB $ 600 $ 130 $ 470
64GB $ 1000 $ 270 $ 730
128GB $ 2600 $ 600 $ 2000

Video: How to upgrade RAM to 5K iMac (2020) version

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Before the upgrade

Before proceeding with this tutorial, you will need to obtain the appropriate memory module. Uses apple DDR4 2666MHz SO-DIMMs, So you will want to make sure that the RAM you purchase is of this type.

I recommend buying OWC RAM, as I have used it in some of my Mac Mini upgrades, Mac Pro upgrades and iMac upgrades and have always had good success with them. However, I have used memory from companies such as Crucial, Nemix, and others with no problems. Then, the main thing is to make sure that you buy the right type of memory – the DDR4 2666MHz SO-DIMM module. If you do this, you should be golden.

You may also want to keep in mind future RAM upgrades. For example, if you only need to upgrade 64GB of memory now, but think that you want to upgrade to a maximum 128GB amount in the future, you want to go for a 2 x 32GB setup. This would leave two SO-DIMM slots that would be available later down the line to add two additional 32 GB modules. While a 4 x 16GB setup will also provide you with 64GB of RAM, it maximizes your available SO-DIMM slots, which complicates future upgrade capability.

Okay, now that we’ve thrown out those housekeeping items, let’s upgrade the IAMAC (2020) RAM.

How to upgrade iMac (2020) RAM

pay attention: This tutorial is only for the 27-inch 5K iMac. This does not work for 21.5-inch iMacs.

Phase 1: Shut down, and unplug all cables from the 27-inch 5K iMac, including the power cable.

Phase 2: Place some towels on a flat surface. Make sure the towels are thick enough and cover a large enough area to accommodate a 27-inch display.

step 3: Gently place the 5K iMac down on the towels, with the display facing down so that the rear of the machine can be easily accessed. Make sure you have enough work space.

step 4: Under the power socket, you will find a button used to dismiss the memory slot cover. To press this button firmly, I use a blunt object (I usually use an ink pen with the pen part), which will open the memory slot cover. Remove the memory slot cover to uncover the four SO-DIMM slots.

Step 5: If you have purchased four SO-DIMM replacement modules, such as in this example when 4 x 32GB is installed for a total of 128GB of RAM, then you will need to remove all existing modules. If you have purchased only two memory modules, you can install the existing pair if you wish, but keep in mind that you install mixed-sized memory in the video walkthrough above.

Depending on your 5K iMac configuration, there may be two or more SO-DIMM slots in use. If you have opted for only 8GB RAM, there will be 2 x 4GB SO-DIMM modules. Push the lever on the sides of the iMac to unlock each SO-DIMM slots, and lift each SO-DIMM module to remove it.

If you ever want to sell your iMac with native RAM, or if you ever need your iMac by Apple, you want to hang on to the RAM module.

Step 6: If you are using only two RAM modules, such as 64 GB (32 GB x 2) configuration, install the module in pairs to take advantage of dual-channel memory. In this case, you want to install each pair of RAM modules in slot 2 and slot 4, or slot 1 and slot 3. This is how Apple’s 8 GB RAM is installed from the factory.

If you are using four memory modules that are all the same, then install all four in the available SO-DIMM slots. Things get a bit weird if pairs of mismatched memory sizes are used. If mismatched pairs of memory are being installed, I think installing one pair in slot 2 and slot 4, and another pair in slot 1 and slot 3 resulted in degraded performance. Notice how the memory speed drops to 2133MHz in this scenario.

Memory speed decreases with mismatched memory pairs

Instead, I found that it is best to install two like modules in slots 1 and 2, and the other two like modules 3 and 4 for best performance. Note how the result of the same memory configured in this arrangement is a speed rating of 2666MHz (2667). Be sure to play the video above for more information.

Be sure to insert all new modules with the notch on the left. Push each module directly into the slot firmly so that it blinks into place. To ensure that the modules are installed correctly, and the lever is locked back in place.

Step 7: Restore the RAM gate by simply pushing it in place. The ram gate is protected through friction, so you will need to press it firmly to reinstall.

Step 8: Move your iMac back to your work area, connect all cables with the power cable, and turn the machine back on. If you see a black screen for an extended period of time, don’t be worried – it indicates that new memory is being initialized.

Step 9: Once MacOS is back on the desktop, go to This → About Mac Memory, and make sure all installed memory is responsible for getting up and running at the correct speed. If not, you have to go back and make sure that the memory is properly and firmly installed in the SO-DIMM slot.


Upgrading your system memory will add a lot of headroom to work with multiple demanding applications simultaneously. This can be particularly beneficial when working with pro-oriented applications such as Final Cut Pro X, Logic Pro X, Screenflow, Affinity Photo, Adobe Creative Cloud, and the list goes further. Among other things, memory steward machines need to write to disk more often, which can slow down your computer, sometimes to an external crawl.

Too much headroom to run multiple applications

But in addition, upgrading your memory can have CPU performance effects as well.

A Geekbench CPU benchmark when running with just 8GB of RAM before a memory upgrade.

This is not a massive improvement, but upgrading 8GB of RAM from stock will improve CPU performance.

A Geekbench CPU benchmark when running with 128 GB of RAM after a memory upgrade.

9to5Mac’s Tech

Easily upgraded memory is one of the things that has given the 27-inch iMac the best value in the entire Mac lineup in years. Not only do you get a high-quality 5K display, but you can also save thousands on RAM. The 5K iMac is a great value-conscious machine, and it was a great run.

However, the reality is that this may be the last significant update to the 5K iMac in this current design. With Apple moving to its own Silicon for Mac, it is highly likely that the next iMac iteration will sport Apple Silicon under the hood, as well as a new modern redesign.

While a redesign is much needed, it is a bit of a bitwatch, as I think there is a possibility that we will see user-accessible RAM thin in future versions of the iMac. I’m not seeing Apple design a completely new chassis right now and have the ability for users to add their own RAM after the fact, especially to move to the in-house CPU with the iMac.

With that being said, if you are planning to buy a 2020 iMac, be sure to take advantage of this amazing capability. I think it’s pretty weird how much RAM Apple charges, but I have to give them the credit for liking users in terms of at least 5K iMac.

At any rate, I always recommend configuring the absolute minimum amount of memory for the 5K iMac during the build process with the idea of ​​upgrading yourself and keeping the saved dollars towards other upgrades. For example, adding more flash storage, upgrading CPU or adding better GPUs. These are all things you usually can’t replace as easily as RAM, and your money is better spent in these areas.

What do you think Are you considering a 5K iMac purchase? Do you think Apple’s future iMac machines will retain RAM cords for user-accessible memory? Sound down in the comments with your thoughts on the subject.

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