Crucial RAM 16GB DDR4 2400MHz CL17 Memory for Mac

Crucial RAM 16GB DDR4 2400MHz CL17 Memory for Mac CT16G4S24AM

Crucial RAM 16GB DDR4 2400MHz CL17 Memory for Mac CT16G4S24AM


Crucial DDR4 iMac SODIMMsodimm iMacspeedquality

Reliability for Mac systems

When you use your Mac system, you expect intuitive, dependable performance. Expect the same out of your memory. Every Crucial module that leaves our doors has been tested at the component level for voltage and temperature resistances, signal integrity, and software compatibility.

Speed for Mac systems

A memory upgrade is the fastest, easiest, and most affordable way to get more performance out of your Mac system. Upgrade your Mac with Crucial memory modules and maximize your creativity with top speed and high density DDR3 and DDR4 memory modules

Support for Mac systems

Unsure how to install memory or have an important question about your Mac system? Let the Crucial experts help! They know Apple systems inside and out and enjoy providing helpful, friendly technical support. Whether it’s phone support, videos, FAQ articles, or do-it-yourself install guides for more than 70 different Mac systems, Crucial has the resources you need to keep your system up to speed.

Micron quality – A higher level of reliability

As a brand of Micron, one of the largest memory manufacturers in the world, Crucial memory for Mac systems is backed by the same quality and innovation that has produced some of the world’s most advanced memory and storage technologies. With a product portfolio that includes upgrades for more than 100,000 systems, we’ve got one specifically designed for your Mac system.



Weight: 9.07 g
Dimensions: 6.86 x 0.51 x 2.79 cm; 9.07 Grams
Brand: Crucial
Model: CT16G4S24AM
Colour: Green
Batteries Included: No
Manufacture: Micron
Dimensions: 6.86 x 0.51 x 2.79 cm; 9.07 Grams

21 Responses

  1. DwayneWallwork says:

     United Kingdom

    I bought this to upgrade my iMac 27 inch 5k retina (bought 2020 but is a 2019 model for some reason) there are four slots and I’d specced it back in 2020 with 16gb of ram. So as my music making got ever more sample based, some of my piano sounds can be 4Gb alone I thought let’s get more ram. Mac says my model will support 64gb of ram so that’s what I bought in two lots of 32gb. I read everywhere that people were getting 128gb of ram to work so I thought I’d just put it into the two free slots. Switched on and it loaded first time and now I have a total of 80gb of ram. Things do load more readily and I’m not getting any warnings on big projects so all is good.
    Oh another thing. This ram is 2666 mhz and Mac state 2667mhz don’t let that out you off, it’s actually 2666.9mhz for both and Mac choose to round up. It now states that it’s all 2667 mhz on the inspector window.

  2. EvanLTXxltqzmmq says:

     United Kingdom

    I wanted to add extra RAM to my 27″ IMac 2020 these are perfect!

  3. Anonymous says:

     United Kingdom

    I always purchase my Mac Memory from Crucial as they provide great service and great prices.

  4. Anonymous says:

     United Kingdom

    Golden Review Award: 2 From Our UsersBought to upgrade my iMac 27″ 5K 2019 3GHz 6-Core Intel Core i5 from 8GB to 32GB as I’ve started to do more video editing and my machine was struggling a bit while using Adobe After Effects.

    Easiest installation ever, worked perfectly as soon as I turned the machine on.

    It feels a lot less sluggish now. I have opened InDesign, Illustrator and Photoshop at the same time (something the machine used to struggle with) and opened various large working files. I can flick between all 3 programs a lot smoother than I used to.

    Very very happy with my purchase.

  5. Jonathan Heller says:

     United Kingdom

    Works perfectly with Apple hardware. I’ve bought two separate kits and the computer has recognised the full 128GB. No prohlem whasoever.

  6. JonahHaveman says:

     United Kingdom

    Have used Crucial before and they are just brilliant. Such an affordable way to increase your RAM, instead of paying eye watering Apple prices. Just look up your computer specs on their website and you can find the RAM you need. So easy to install, a child could do it. Just remember to touch something to ground yourself prior to installation, so you get rid of any unwanted static while you complete the operation. Have updated all my Macs by using their RAM. Never had a problem, so happy to recommend. Quick delivery and always reliable.

  7. Anonymous says:

     United Kingdom

    Golden Review Award: 2 From Our UsersThese were bought to upgrade the memory of a 2020 27″ iMac from 8gb to 64gb. I decided to remove the existing memory as I wasn’t sure about compatibility with speed and thought an extra 8gb is not going to make a lot difference since I’m sticking 64gb in.

    There is an easy to remove cover at the back of the iMac, a couple of springy clips allow you to move the memory carriage into an accessible position. The old memory just lifts out and the new memory slotted in the same place. It took longer to remove all the connections at the back of the computer than it did to replace the memory modules.

    If you need to check what memory is in your iMac click on the Apple (top Left), select About then select memory and a graphic shows you what memory modules you have and which slot they are in. Slots 1 & 3, and slots 2 & 4 are paired and need the same memory modules in each one of the pair, though 1 & 3 can have different RAM values from 2 & 4. So I put each of these two 32gb modules in slot 1 and slot 3.

    When I turned everything back on the iMac worked as if nothing had happened, but I ran a Photoshop test that was taking 4 minutes with 8gb RAM. It was now almost instant with the 64gb RAM upgrade, so I’m very pleased with my purchase.

  8. EnriqueReiniger says:

     United Kingdom

    As an old school graphic designer that uses Adobe CC software for print and digital, I’ve always been on the lifelong learning curve with tech that is several steps/planes ahead of where I am right now. Most of the time this does not inhibit my day to day use of the main software tools but having speced my Apple desktop Mac with the maximum RAM capability I found that in the age of remote working and being networked so much of the time that this phenomenon more than anything slows down the machine when my broadband connection becomes not so broad after all.
    The moral of this story is that to get the best out of this product is to be offline as much as possible.

  9. What Hi-Fi? says:

     United Kingdom

    I bought this RAM as I wanted a single 32GB DDR4 SODIMM stick for my new Framework laptop (DIY Edition i5) and it was ~20 cheaper than the equivalent non-Mac sticks. Contrary to the ‘official’ answer to a question about using this in a non apple device – it works fine, as it’s standard DDR4 SODIMM. Full 32GB detected and usable by Fedora on my laptop, no issues. I wouldn’t use non-Mac RAM in Macs however as they can be very fussy about tolerances and error checking.

    5.0 out of 5 stars Great value - Ignore marketing, not only for Mac, works fine in Framework Laptop

  10. JimmieRowntree says:

     United Kingdom

    Bit of,a bargain at this price, (125), bought to upgrade a recently purchased iMac.
    Went from 16 to 40Gb and notice a lot of difference. Start up times appear to have reduced and no slowing or spinning beach ball when having numerous windows open.

    I use proprietary structural engineering software running under windows 10 in a virtual environment (parallels) with native Mac AutoCAD, as well as MS office and a other bits and pieces.

    Since upgrading I can run a windows on one screen and a Mac screen without any loss of speed, brilliant.

    Excellent value and a brilliant, simple upgrade.

  11. Anonymous says:

     United Kingdom

    I bought a 2020 iMac 27″ but was astounded at the price for RAM upgrades – so after a bit of a web search I found this as a viable RAM upgrade option.

    I was not disappointed in any way at all – it took me literally 2 minutes to install this and my Mac now runs like the powerhouse it should do, at a fraction of the cost that I would have paid if I had bought this direct.

    If you have upgradable RAM options in your Mac, do this now! I can now run GPU-intensive activities like photoshop and indesign in a flash and they run simultaniously without any lag whatsoeve

  12. Anonymous says:

     United Kingdom

    Golden Review Award: 3 From Our UsersHaving recently purchased one of the last 2020 27″ iMacs from Amazon I thought it best to future-proof it as best I can, so purchased some additional RAM for it bearing in mind it only had 8GB, so purchased this Crucial CT2K16G4S266M 32 GB Kit which consists of 2 off 16GB DDR4 2666 Ram chips.

    Unlike the smaller 21.5″ iMac and some of the newer models, the Ram in the 2020 27″ iMac can be easily upgraded, and yes I can confirm that it’s very easy to do and has resulted in the RAM going from a paltry 8GB to a far more impressive 40GB because the old RAM chips can be retained.

    Sure the new iMacs are coming out, but they seem to be missing ports on the back, and realistically I’m not going to be rendering 5K videos for the foreseeable future, mainly YouTube, emailing, and some photo editing, so have purchased Affinity photo editing software so am well sorted.

    This has to be one of the easiest fixes to speed up your computer and will future-proof it for many years. The Crucial RAM upgrade has to be one of the best buys at the moment, and aside from changing the HDD to SSD or using an external SSD to store your files on if you have a tiny internal SSD drive there aren’t really a lot of other steps you can take to make your computer run faster.

    Highly recommended if you have a 2020 (or older) 27″ iMac and want to speed it up a bit.

  13. Anonymous says:

     United Kingdom

    I purchased a iMAC 27inch 5k 2020, with 8gb Ram installed, purchased 2 x 8gb to take me to 24gb I’m not a gamer but a 62 yr old female geek! figured I’d upgrade it so the setup will last me a while.
    it was a breeze to install.
    if i can install it anyone can!

  14. Anonymous says:

     United Kingdom

    I got this for my iMac 2020 5k 27″. It took me less than 5 minutes to install and works perfectly. It has really reduced the memory pressure in the activity monitor. I removed the existing sticks and put the new ones in the original slots. 32 GB might be a bit overkill for for the music production that I do but it’s there if I need it. I would definitely recommend this product.

  15. HenrietHuxley says:

     United Kingdom

    If you use Apple computers you’ll know that they charge exorbitant prices for RAM which has to be installed by their technicians on most (but not all) of their computers. It’s why I bought an Apple iMac, a rare exception for which you can easily buy your own RAM (from Crucial) to install yourself without voiding your warranty. Apple would charge me 600 for 32GB of this RAM whereas Crucial will sell me exactly the same Apple approved 32GB of RAM for 140.

  16. Anonymous says:

     United Kingdom

    I was very sceptical about upgrading the memory on my beloved iMac, but took the plunge after new year as this was my resolution to fix it. It was becoming unbearable slow and unresponsive to typing and general functionality
    The installation process was simple, quick and effective
    Wow what a difference!
    I can now type in “real-time” rather that waiting for the Mac to catch up and can have more that one program open at a time
    Cannot praise enough – thank you for giving my my sanity back…

  17. Johanna57E says:

     United Kingdom

    Golden Review Award: 5 From Our UsersArrived with Prime fast, works perfectly as I used the Crucial UK website to identify the best modules to use and they provided a link to Amazon to buy the right ones.

    iMac 2019 27inch 5k Retina Model – existing base capacity 8GB; increased to 24GB.

    You can mix modules, you have to buy a kit or twin modules to fill in the two remaining slots.
    Gen. rule of thumb about RAM – buy in pairs and always fill in all available slots. 2 slots should remain free, never none or odd numbers i.e. 1/3.

    If you want to optimise you always put RAM with the highest capacity in the bottom (Bank 0) and 3rd (Bank 2) from the bottom. Then the original RAM modules swap to the new positions of slot 2 (Bank 1) and 4 (Bank 3).

    Where my pre-installed 2 NR 4GB modules were I swapped with the NEW 2 NR 8GB modules. And then put the already pre-installed 2 NR 4GB modules in the 2 remaining slots.

  18. Anonymous says:

     United Kingdom

    Golden Review Award: 4 From Our Users** 2019 27″ 5k iMac**

    Firstly, this was put into the NEW 2019 iMac as above. I can confirm it works perfectly, no issues.

    PLEASE NOTE: I made a mistake in purchasing only one of these as I thought they came in pairs. That’s my fault but they offer these in pairs slightly cheaper, but no big deal. They must be in pairs! I just didn’t read it properly.

    Anyway, once I had both they are very easy to install (5 mins) and a reboot and you’re off! I placed the new pair in the empty slots and left the original RAM from Apple (X2 4GB sticks) in the original slots they came in. So simple, and I now have 24GB RAM for less then 90. Speeds things up and will be future proof for some time now. Highly recommended.

  19. Anonymous says:

     United Kingdom

    Golden Review Award: 2 From Our UsersI purchased this to upgrade the RAM on a 2017 5K iMac 27″. I’ve used Crucial before on other Macs (MBP and Mini) and have always found the quality to be good for the price. Although the iMac 27″ has a hatch at the back of the screen to make RAM updates easy, it was a little trickier than I had expected to get the RAM recognized by Mac OS.

    My iMac came as standard with 8GB (2 x 4GB), so I put the RAM cards into the 2 empty slots. Upon starting, the iMac came on, but gave a permanent black screen. I then tried to reset the NVRAM/PRAM as others have explained, but this didn’t work. I took out the RAM cards and replaced again because some reviewers suggested it is hard to get a snug fit into the iMac RAM slots. I again performed a NVRAM/PRAM reset. I actually thought that this had failed again and whilst trying to find the Crucial Helpdesk number realized that the iMac flickered to life. As such, I think a degree of patience is required for the Mac OS to recognize the new RAM upon first installation…. Never had this problem with either my MBP or Mac Mini, but then again, these were straight replacements, whereas this was to install new memory into the 2 empty slots of the iMac. I’m very happy with the performance of the iMac now – 40GB should be more than enough for my current statistical analysis and computational modeling needs.

  20. MiaJacquez says:

     United Kingdom

    I had 16GB installed in my iMac 27 inch 2017 4.2Ghz i7, and then installed 32GB on top of that. I am lazy and keep 40 or so web pages open at any one time. I can switch between Word, Powerpoint and Safari and Firefox and rarely get system hangs. If they do happen, it is my fault for being lazy for not shutting down somethings when I have truly finished with them.

    Installation was fairly easy, but not a complete breeze. Read what others tell you about this.

    I am very happy and a lot less frustrated.

  21. Anonymous says:

     United Kingdom

    Golden Review Award: 19 From Our UsersCrucial CT2C16G4S24AM 32 GB Kit (16 GB x 2) (DDR4, 2400 MT/s, PC4-19200, DR x8, SODIMM, 260-Pin) Memory for Mac

    My machine is a 27″ iMac 5K, mid-2017 model, 4.2GHz i7 processor and I was looking to upgrade on the original 8Gb memory. I was concerned that when one reviewer recorded that this memory hadn’t worked for them, I might suffer the same problem, though when I researched the Crucial website, the indication was that this part number should work.
    The original memory modules were inserted in locations 2 & 4 (counting “1” from the top of screen). When this (CT2C16G4S24AM) memory arrived, and I installed the modules in the empty 1 & 3 locations, I disappointedly found that the Mac wouldn’t boot up.
    After a call (0800 091 0021) to Crucial Technical Service, the very helpful agent confirmed that the part number should indeed work. I’m happy to say with a bit of perseverance, and great guidance from the agent, we found that by inserting the new modules in position 1 & 4, and the original modules in positions 2 & 3, my Mac booted up and found the full 40Gb.