Buying a New iMac? Here’s What You Need to Know About 2017 iMac RAM Upgrades

Apple finally released a long-awaited upgrade to the iMac this week, announcing new models based on Intel’s latest “Kaby Lake” platform. This switch to the newer CPU and chipset means that the 2017 iMacs now require DDR4 RAM, which is important to know for those who plan to upgrade their Mac’s memory after purchase.

Here’s the info that RAM upgraders need to know for the 2017 iMac and the upcoming iMac Pro.

2017 iMac RAM Upgrade

First, like the older models, those purchasing the 21.5-inch iMac are out of luck when it comes to user RAM upgrades. Starting with the 2015 iMac update, Apple solders the RAM to the logic board for the 21.5-inch models, making user RAM upgrades practically impossible (Update: iFixit has discovered that the RAM and CPU in the 2017 21.5-inch iMac are once again socketed, making RAM upgrades possible, but difficult and warranty-voiding). This means that if you think you’ll need more RAM than the stock 8GB, either now or in the future, you’ll need to shell out the cash up front to ensure that your new iMac remains viable in the years to come.

The 27-inch iMacs are a different story. While each year we fear that Apple will take away the ability for user upgrades, the 2017 iMacs thankfully retain the four user accessible RAM slots.

The new iMacs ship with 8GB of 2400MHz DDR4 memory (2x4GB) in the default configuration. For those who want to upgrade, the entry-level i5-based iMac supports up to 32GB of 2400MHz DDR4 (PC4-19200) 260-pin SO-DIMMs (4x8GB), while the mid-range i5 and i7 iMacs support up to 64GB of the same class of memory (4x16GB).

imac ram door

Because the new iMac has the same external design as its predecessor, the actual process of upgrading RAM remains quick and easy. Users can simply pop open a small door beneath the rear vents on the back of the iMac to reveal the four RAM slots. If you’re upgrading to the maximum 64GB, just remove the stock 4GB modules and replace with your new modules.

imac ram upgrades

As long as your new RAM has the correct specifications, your iMac will boot right up after the swap and you’ll have instant access to your increased memory.

As for why you’d want to upgrade your new iMac’s RAM yourself, the answer is easy: price. Apple is currently charging $200 to upgrade your iMac’s RAM from 8GB to 16GB at purchase. You can achieve the same result by adding 8GB (2x4GB) after purchase for just $65.

imac ram prices

On the other end of the spectrum, Apple charges $1,400 to upgrade to the maximum 64GB at purchase. You can buy the same upgrade (4x16GB) for about $580. So if you’re considering a new 27-inch iMac and want more than the stock 8GB of RAM, consider performing this easy upgrade before shelling out for Apple’s highly inflated memory prices.

iMac Pro

Unfortunately, all of the points made in the previous section go out the window when it comes to the upcoming iMac Pro. This new powerhouse iMac will feature up to 18-core Xeon processors, Radeon Vega graphics, huge amounts of NVMe flash storage…but it apparently won’t have user-upgradeable RAM.

Without further clarification from Apple, the reason for the change is likely due to the fact that unlike the “standard” iMac, the iMac Pro utilizes ECC memory. And, while detailed technical specifications for the system have not yet been released, Apple’s promotional materials for the design appear to show full-sized DIMMs, as opposed to the smaller “mobile” SO-DIMMs used in the standard iMac.

imac pro components

Apple’s promo images appear to show socketed full-sized DIMMs.

This required Apple to move the location of the memory modules, and because the iMac Pro shares the same basic chassis design as the standard iMac, that little door on the back of the case is no longer useful.

The good news, however, is that based on the image above, those ECC memory modules still appear to be socketed and not soldered. This means that while the RAM upgrade for the iMac Pro certainly won’t be as easy as the standard iMac, it still may be user upgradable for users willing to take the time and risk to pry open their expensive system. Of course, this is based solely on early promo images, which may not represent the final design of the iMac Pro. We’ll need to wait for confirmation from Apple, or for these systems to hit the market in December, to know for sure.

16 thoughts on “Buying a New iMac? Here’s What You Need to Know About 2017 iMac RAM Upgrades”

akifa says:
Good artical. Buy Now Amazing offers on iMac 27-inch best price in india,imac with Retina 5K display,3.4GHz quad-core Intel Core i5 (2017 Model) .Appworld is providing Best Discounts on imac. AppWorld offers Emi,daily deals,shopping & quality online At delivery.
Dave Finton says:

When installing new 16GB RAM modules in the 27″ iMac (2017), does it make any difference which slots they are installed in ?

I’ve seen some that maintain the new modules should go in slots 1 and 3. Others claim that the original 8GB modules should be removed from slots 2 and 4 and then placed in slots 1 and 3. Then the new 16GB modules are placed in slots 2 and 4.

Is there any advantage either way?

Bjarke Strøm says:
Hi, sorry for being slightly off-topic (and possibly stupid…;- ), but can higher clock-speed ram be used, 2400 mHz seems low in terms of DDR4….?

-If not, then why….?

ducatista says:
Hi there,

I’m planning to upgrade the memory on my 2017 27″ iMac from the standard 8GB to 20GB by way of 2x8GB aftermarket modules (I had been waiting for Crucial’s RAM to get back in stock – but thanks to your site, see that MacSales/OWC has modules in stock). Two questions – 1) I’ve always been a Crucial customer for memory – is OWC comparable in reliability and quality? and 2) I’ve read elsewhere that it’s ideal to match RAM modules in size for best performance, but right now would like to maximize cost effectiveness of using existing 2x4GB RAM with 2x 8GB added…is this okay for performance/computer health?


Bruce Wayne says:
Why can’t I install 64 gb on the entry level 27″ iMac?
TekRevue says:
Turns out that you can. We don’t know why Apple says you can’t, but OWC confirmed that it works with third-party RAM upgrades.
Onias Righi says:
hey, is that true???? thats an awesome news… I just bought a new 27″ and is the entry level… and I just want to install more than 32GB… what kind of DDR4 do I have to buy?.
LiveJoX says:

1. Any number of DIMM modules can be used? For instance, just one 16 GB DIMM module leaving the other three slots empty?

2. Any special sorting order for DIMM modules in slots of same of different sizes (mixed or not) filling or not all four DIMM slots?

yrsmi says:
Hey sorry in advance if I sound like a complete noob, but can someone tell me if I can add a 3000mhz ram (16g) along with the two standard 2400mhz (4gb) that the iMac came with?
justbobf says:
You know, one would think that RAM in the Pro version would be user upgradeable. If the RAM is off to the side, Apple could just as easily install a door at that location. Will, they? is another question.
Jitendra Vaswani says:
Will a 2 x 8 GB work along with a 2 x 16 GB in iMac 27 inch ?
TekRevue says:
Dave Markham says:
Does anyone know if the 27″ RAM hatch is still accessible on the built-in-VESA-adapter (i.e. no stand) models?
TekRevue says:
Yes, it is. The VESA mount does not interfere with the hatch, so it operates exactly the same as the regular model.
Dave Markham says:
I appreciate the quick reply @tanousjm:disqus . Thank you!
Raul says:
Is MacSales a reputable vendor? Should I expect the same performance if I buy an OWC 32GB upgrade kit than if I buy an iMac that comes preloaded with 32GB directly from Apple?
TekRevue says:
They’ve been around since the late 1980s, and I’ve never had any problem with their products. Their SSDs, in my opinion, are no longer the best option compared to the latest drives from Samsung, but their RAM quality and prices are great. The specs on the RAM are the same so you won’t see any performance difference between their memory and Apple’s, but if you have an issue, OWC support is top-notch.

To be clear, TekRevue has run ads for OWC in the past, but has no current relationship with the company.

Jerry Suppan says:
Out of curiosity, can 32GB x 2 memory modules be used in lieu of 16GB x4? And if so, would there be any particular reason to want to do so? Thanks.
TekRevue says:
iMacs have a history of “unofficially” supporting more memory than Apple claims, so the benefit of using 32GB modules would be that you could theoretically upgrade to a total of 128GB in the future. However, I don’t believe that 32GB DDR4 SODIMMs are available yet, or if the iMac will support them once they are.
Jerry Suppan says:
Thanks for that quick clarification. I was perusing pricing for memory modules and noticed 32GB modules exist. But after receiving your reply I relize those are RDIMM modules and not SODIMM. Thanks for the heads up clarification.


Stephen Whittenburg says:
How many RAM slots are there on the entry level iMac 27″? I know that one only supports up to 32GB, so I didn’t know if there were just two slots, unlike the four slots in the mid and high end. Thinking of getting the base 8GB and wasn’t sure if I bought another 8GB of RAM aftermarket if there would be a place to put it, or if I’d have to buy 16GB of RAM aftermarket and replace the factory RAM in order to achieve 16GB RAM
Peter Latzenhofer says:
Can I add to a 8GB Model (2x4GB) another 32GB (2x16GB) of (3rd Party RAM)? So it ends up at 48GB? I have an “old” 2013 iMac and added to the default 8GB (2×4) additional 16GB (2×8) and it worked perfectly so far…Is there anything I have to take care of?
TekRevue says:
Yes, that will work, although you’ll end up with 40GB total, not 48GB.
alex persegona says:
Yeah, I was thinking that was a mistake on Apple’s site when I did a search for the “pc4-2400” RAM and nothing was coming up. Thank you for clarifying that.
TekRevue says:
That’s a typo on Apple’s part. There’s no such thing as “PC4-2400” RAM (well, technically there is, but it refers to a specification on an old type of RDRAM which is not at all compatible with the iMac). Whoever updated that page for Apple mistakenly put the speed value (2400MHz) in place of the memory’s rating (19200). So it should be DDR4 2400MHz (PC4-19200).

Leave a Reply

Your email address will not be published. Required fields are marked *

Disclaimer: Some pages on this site may include an affiliate link. This does not effect our editorial in any way.

Todays Highlights
Zoom How to Change Name