iMac (Retina 5K, 27-inch, 2017) CPU and NVME SSD Upgrade Pitfalls and Tips

Discussion in 'iMac' started by rxs0, Apr 13, 2019.

  1. rxs0, May 5, 2019
    Last edited: May 5, 2019

    rxs0 thread starter macrumors member


    Apr 4, 2019
    Should work fine. Let us know how the upgrade goes.

  2. rxs0 thread starter macrumors member


    Apr 4, 2019
    With high loads, my system fan turns on anyways with my i7-7700 CPU. I will post some CPU temps while idle and under heavy loads soon.

    Retrospectively, I would install the i7-7700K if you can. Be sure to apply a very good thermal paste such as Arctic Silver 5 or Arctic MX-4.

  3. chrispri, May 5, 2019
    Last edited: May 5, 2019

    chrispri macrumors newbie

    May 4, 2019
    I also installed the 7700k with the Noctua thermal paste. The CPU temp is between 37 and 97 degrees. Tested with the 'yes'-command.
  4. djangoreinhardt442 macrumors member


    Apr 6, 2019
    Was debating between the IC Thermal pad made from graphite which I have
    The thermal grizzly Kryonaut

    The grizzly product is supposed to have the best conductive properties.
    I have read a few reports where people de-lid their 7700K, use liquid metal, and then re-lid and use quality thermal paste and achieve drop in maximum, under load temps from 95-100 to 75 degrees
    Then again, I am not sure I want to play around with delidding and liquid metal (corrosion of metals, electrical conduction, etc.).
    Decisions, decisions...(yeah..first world problems, I know).
  5. rxs0, May 5, 2019
    Last edited: May 8, 2019

    rxs0 thread starter macrumors member


    Apr 4, 2019
    I would probably just use the stock i7-7700K CPU with a good thermal paste, such as Silver 5 or Arctic MX-4. The liquid metal is potentially risky in regards to corroding the metal surface of the CPU and copper of the Apple heatsink. Also, since liquid metal is electrically conductive, if the liquid metal leaks outside of the CPU, it can short out and burn out the electronics in the logic board. It's probably not worth the risk given the marginal benefits.

    The guy in the videos below de-lidded the cpu and used liquid metal. You might want to ask him about his results via a comment in his YouTube videos. Let us know what you decide to do.

    Also, please see post by cynics regarding use of liquid metal.

  6. timbloom macrumors 6502a


    Jan 19, 2002
    My god, I’ve been waiting a year to see something like this and somebody brave enough to risk it. I appreciate your efforts and guidance, it really goes above any beyond.

    I know almost everyone here is looking at the Samsung drives, the intel p660 is half the cost and I really don’t need extreme performance. I absolutely must get better performance than my fusion drive.. it’s horrible and the iMac has sat unused a year because of my frustrations with it.

    Would it be a safe or risky assumption to say that the intel should work similar to your experience here?
  7. rxs0, May 5, 2019
    Last edited: Jun 18, 2019

    rxs0 thread starter macrumors member


    Apr 4, 2019
    Updates regarding successful Intel 660p NVMe drive upgrades in iMacs:

    This member, mdelrossi has successfully upgraded his iMac with the Intel 660p drive. See posts below:

    Another successful NVMe upgrade using the Intel 660p drive, MacManSuite.


    Although this is not an exact match (MacBook Pro vs iMac), here is an excerpt of a list of compatible NVME drives used in upgrading the Macbook Pro (see post below). The Intel 660p drive should work.

    Which NVMe SSDs are known to work?
    You will need to buy a M.2 adaptor for all the below SSDs :
    • Adata NVMe SSD : SX6000, SX7000, SX8200, SX8200 Pro etc.
    • Corsair NVMe SSD : MP500, MP510
    • Crucial NVMe SSD : P1
    • HP NVMe SSD : ex920, ex950
    • OCZ RD400 (and all Toshiba XG3-XG4-XG5-XG5p-XG6 line)
    • Intel NVMe SSD : 600p, 660p, 760p etc.
    • MyDigital NVMe SSDs : SBX - BPX
    • Kingston NVMe SSD : A1000, A2000, KC1000
    • Sabrent Rocket
    • Samsungs Polaris NVMe SSD : 960 Evo, 960 Pro, 970 Evo, 970 Pro
    • WD Black NVMe SSD v1, v2 and v3
    • Samsung 970 Evo Plus (now works with new firmware released May 20, 2019!) See first post of this thread.
    NVMe SSD known not to work on MacBook Pro / Air. DO NOT BUY:
    • Samsung PM981
    • Samsung 950 Pro
    • Samsung 970 Evo Plus *Update May 20, 2019* This drive now works with the new firmware. See first post of this thread.

    Also review this post for other successful NVME drive options:

    iMac 2013 (and later) with NVME SSD?

  8. djangoreinhardt442 macrumors member


    Apr 6, 2019
    You need to state your make and model of iMac

    Also list all the specs.

    Of course the intel 660p will do. I just saw a deal for 1tB 660p for less than 100 bucks

    Get a late generation sintech adapter
    Update to latest version of Mojave
    Do a time machine backup

    Read ALL the information provided and make sure you have all the tools needed for disassembly

    Install your 660p nvme SSD

    Let us know how it goes
    --- Post Merged, May 7, 2019 ---

    Ooops. You don’t NEED to state anything. That came off wrong.

    I was merely suggesting that you COULD state your specs and model. :).

    Small difference
  9. alexdd macrumors member

    Oct 26, 2012
    Can you post the benchmarks with AJA app but with 64 GB file size?
  10. rxs0, May 8, 2019
    Last edited: Jul 17, 2019

    rxs0 thread starter macrumors member


    Apr 4, 2019
    2019 iMac Retina 5K, 27-inch CPU and NVMe SSD Upgrades

    Update May 23, 2019:
    From Zach on regarding 2019 iMac 27-inch NVME and CPU upgrade:

    "Hey Rich! I just had a heck of a time trying to upgrade my SSD in my 2019 27” iMac. Turns out the 1TB WD Black and the 1TB 970 PRO NVMe’s didn’t work in mine, still not entirely sure why.

    However! The 970 EVO 2TB and the Sintec NVMe Macbook air 2013 adapter worked flawlessly with an internet restore boot option.

    I also upgraded to a retail i9 9900k and everything works flawlessly!"

    I have uploaded his pictures as well.

    Thank you so much Zach for sharing with us!



    The 2019 iMac Retina 5K, 27-inch differs from the 2017 27-inch iMac by (4) main changes:

    1. Different WIFI/Bluetooth architecture, with a new small detachable metal antenna cowling. The layout, disassembly, and reassembly are otherwise the same, with the system still using the same (2) T5 screws and antenna connectors. Antenna tool 923-01322 shown in picture below.
    2. Different Logic Board Battery layout. Negative side (no markings) of battery (BR2032)
    faces the metal clip.
    3. Different Diagnostic LED layout, still (5) LEDs total. See first post in this thread for LED interpretation.
    4. Different GPU Spring systems, depending on system: (Thanks to Babak for update.)
    - In first video below by Babak, the GPU mounting system is the same as the one in the 2017 iMac system. This is the 3.7GHz 6-core 9th-generation Intel Core i5 processor, Turbo Boost up to 4.6GHz iMac with Radeon Pro 580X with 8GB of GDDR5 memory, 27-inch iMac.
    - In the second video below, the GPU spring looks a lot like the one used in the iMac Pro system. This is the 3.6GHz 8-core 9th-generation Intel Core i9 processor, Turbo Boost up to 5.0GHz with Radeon Pro Vega 48 with 8GB of HBM2 memory, 27-inch iMac.

    The disassembly and reassembly of the 2019 iMac 27-inch otherwise appears to be very similar to the 2017 27-inch iMac.

    Successful 2019 iMac Upgrades:
    - macmanss has recently upgraded his 2019 27-inch iMac to a 2TB Samsung EVO 970 NVMe drive.


    Attached Files:

  11. Yatheesh macrumors newbie

    May 12, 2019
    Now its time to swap CPU's to 8/9th gen ones!!
    Atleast on 2TB fusion drive model!!
  12. rxs0 thread starter macrumors member


    Apr 4, 2019
    Unfortunately, the 2017 iMacs only take 7th generation Intel CPUs, with the highest CPU being the i7-7700K.

    The 2019 iMac however do allow for 8th and 9th generation CPUs. I am assuming the low end 2019 iMac model has the same logic board as the i9-9900K iMac model.

    Not sure if I should get an iMac Pro or one of these 2019 models. I will probably wait for the new iMac Pros, which hopefully will come out later this year.
  13. rxs0, May 13, 2019
    Last edited: May 14, 2019

    rxs0 thread starter macrumors member


    Apr 4, 2019
    It turns out the 2017, 27-inch Retina 5K iMac (with upgraded i7-7700 processor and 2TB 970 EVO NVMe Samsung M.2 SSD) can be successfully upgraded to 128GB of Samsung DD4 2666MHz SODIMM ram.

    See attached photos for Benchmarks without Content Caching

    Enabling Content Caching results in slightly lower benchmarks.

    The AJA Systems Test was run with 64GB Test File Size per request above.

    (4) Samsung 32GB DDR4 2666MHz sodimm of ram (M471A4G43MB1-CTD) in my 2017 27-inch iMac, with no problems.

    Again, I'd rather buy the 2666MHz ram instead of the 2400MHz ram in case I upgrade to the 2019 27-inch iMac.

    In case you haven't noticed, the price of ram has dropped significantly. You might want to wait a few weeks/months as the price of ram is continuing to drop.

    Samsung 32GB DDR4 2666MHz RAM Memory Module for Laptop Computers (260 Pin SODIMM, 1.2V) M471A4G43MB1


    Attached Files:

  14. mdelrossi macrumors regular


    Jun 22, 2005
    Thanks for the detailed description of teardown and all the little things.

    I lost the 3tb drive in my late 2014 5k 27” iMac, and said “hey I can do that!

    So I picked up an intel 1tb blade some liquid metal( I figured if I’m going in, I might as well do the works.), 2tb Ssd ad the required tools and adapters.

    De-lided the 4790k, used the liquid metal,and resealed it. Now this is where I got stuck.

    Do you have any tips on how to put the Heatsink back on easily? I ended up bending a few pins on the socket, and it wouldn’t boot up.
    Took it apart again , found the problem and was able to bend the pins back.

    One thing I did do was to take the ram shroud off, that gave me a bit more room to place the Heatsink and flip it over.

    Second time was a charm. All is working now.

    However the Ssd blade is only running at 2x, is that all there is in this machine?

    Thanks again.
  15. rxs0, May 14, 2019
    Last edited: May 14, 2019

    rxs0 thread starter macrumors member


    Apr 4, 2019
    Intel i7-7700 CPU Thermals using Intel Power Gadget:

    Model Name: iMac
    Model Identifier: iMac18,3
    Processor Name: Intel Core i7
    Processor Speed: 3.6 GHz
    Number of Processors: 1
    Total Number of Cores: 4
    L2 Cache (per Core): 256 KB
    L3 Cache: 8 MB
    Memory: 128 GB

    New firmware as of May 13, 2019:
    Boot ROM Version:

    SMC Version (system): 2.41f1

    Old firmware:
    Boot ROM Version:

    SMC Version (system): 2.41f1

    Temperature: 41 C (105.8 F)
    Fan Starts: 95 C (203 F)
    Peak Temperature: 96 C (204.8 F)
    No instability or crashes during tests. The system is running very stable.


    Attached Files:

  16. djangoreinhardt442, May 23, 2019
    Last edited: May 24, 2019

    djangoreinhardt442 macrumors member


    Apr 6, 2019
    I believe you are limited to pci-e 2.0 x4 on your mac, not 2x...can you send a screenshot of what you see under nvmeexpress?
    You can go look at

    but your mac will not support more than pcie 2.0 x4 so you cannot get more than ~ 800Megabytes a second (I have to go check the math on that one).

    Either way, show us what you mean by "2x".
  17. jonegran01 macrumors newbie


    May 23, 2019
    I just want to say thank you to everyone that has contributed to this thread. It's been immensely helpful as I think about doing the upgrade myself. I just want to get peoples' thoughts on this idea because it is the only thing keeping me from buying the parts and getting to work:

    What's the likelihood that Apple decides to update their OS one day that matches serial numbers on your board to the type of cpu/internal components you have, and proceed to lock you out or disable your computer? It might be a stretch, or it might be completely plausible. Apple has had some interesting business practices in the past. Is this even a possibility? Just interested to get others' opinions on the matter!
  18. retta283 macrumors 6502a


    Jun 8, 2018
    Kingman, AZ
    I don't think it's likely that existing Macs would be affected. Maybe Macs with T2 chips, but even then I don't know. Maybe ARM Macs will have a limitation of that kind.
  19. chrispri, May 31, 2019
    Last edited: Jun 1, 2019

    chrispri macrumors newbie

    May 4, 2019
    Does anyone know if its possible to install a apple ssd with model number MZ-JPV5120/0A4? This is one from a 2013 Macbook Pro Retina.

    With my Samsung 970 Evo 500GB I get the following results in Blackmagic Disk Speed Test:
    1GB: w: 2500 MB/s, r 3000 MB/s
    3GB: w: 1300 MB/s, r 2900 MB/s
    5GB: w: 850 MB/s, r 2900 MB/s

    Is this OK? 5GB seems very slow to me.
  20. timbloom macrumors 6502a


    Jan 19, 2002
    I am just reporting back to say I’ve had success with the intel 660p in my 27” 4.2GHz mid ‘17. I used the newer adapter here as well as the heatsink. Not really sure if I should have done the heatsink, it does make it all sit a little strange. Either way I have no technical issues with it. I do feel like the fan kicks up more than before, but that may be perception only as I am using it more now so notice more. I made the mistake of letting the display adhesive cover the mic hole t the bottom of the display, so my mic is muffled. I will be addressing that eventually but it’s not a priority in the slightest. I left the 2tb 7200rpm drive as a time machine destination, and I’ve had to make 0 changes to my hardware settings. I don’t normally use sleep since I run a 3D printer off the iMac most of the time, but reloading my machine as part of the process re-enabled sleep so I know it works. Unfortunately only after it ruined a couple prints by sleeping during them did I realize time machine didn’t bring my old power settings over.

    Either way, I’m much happier with this computer now.
  21. Sami_UDM macrumors newbie

    Jul 2, 2019
    Can someone (@rxs0) please provide some insight into which 27-inch models can be upgraded to the 9900k? There are discussions that only the 3.1 GHz and 3.7 GHz i5s are upgradeable, although it makes little sense in my eyes, since one of them should be the 8500 and the other the 9700...
  22. djangoreinhardt442 macrumors member


    Apr 6, 2019
    This 9900k should only be possible on the latest imac 2019.
    Someone has a full breakdown on the web
    I believe that it can be done as socket is the same and the motherboard/logic-board is the same. Nothing much to it, other than thermals!!!
  23. Sami_UDM macrumors newbie

    Jul 2, 2019
    My question again, just to clarify: Can the i5-8500k be upgraded to a 9900k or only the i9-9600k?
  24. imac25ssd970evoPlus, Jul 6, 2019
    Last edited: Jul 6, 2019

    imac25ssd970evoPlus macrumors newbie

    Jul 6, 2019
    hi rxs0 Thank you very much for your work and experience.

    I have iMac (Retina 5K, 27-inch, Late 2015)

    I bought: M2 SSD SAMSUNG 970 EVO Plus M.2
    It is written on the production date 2019. 06 Maybe it already has a new firmware?

    I have not bought an adapter yet. I'm at a loss and have already begun to desire that I did not buy a simple SAMSUNG 860 EVO SSD 2.5.

    Should I start disassembling, I have no experience.
  25. ex3m82 macrumors newbie


    Dec 17, 2015
    Does anyone know can WD SN750 with OEM heatsink fit iMac 5k?

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