Chosen Solution

I am looking to buy the 27” iMac 5k 2019 but I can’t find a shred of info on if the CPU is socketed (upgradable) or soldered. Does anyone know? Thanks! -Zach

I got a little impatient and decided to open it up today before my SSD arrived. Good news though! Our thoughts were correct! The CPU is socketed (upgradable) in the 2019 27” iMac. :D I powered it on and booted up the OS and everything ran smooth as butter with the newly installed i9 9900k. I just need to get my SSD so I can close it up and start using it. Thank you everyone for all your input and advice! Chalk this up as another win for the repair revolution :D -Zachary

The 27” iMac’s have always had socketed CPU’s. The 21.5” models low end models often had soldered CPU’s But! You have been limited by the EFI to the CPU’s within the series . So in this case iMac19,1 Series CPU options.

iMac 27 2019 Can be upgraded to i9-9900kf or i9-9900k I9-9900kf has better performance. Can be upgraded from 3.0 base model to 3.7 high end model. I done it 3 times already. Remove battery from mother board on 3.0 base model while installing i9-9900kf After install reinsert battery. Update (10/26/2019)

here the proof

Morning Guys, I kinda used this thread as the catalyst to go ahead and upgrade my base 27-inch 2019 (only bought last week to be fair). I wasn’t convinced that the i9-9900KF or other higher spec processor would work. Its a big lay out for a punt. So I opted for the i9-9900K. £450 new. I opted for this processor due to this being an option straight from Apple. Anything googled online only really suggests the board supports 4 options. I also upgraded the RAM to 64gb but while is was in, installed a 1TB SSD and 128GB PCIe blade (that I had spare which came out of a 2015 MacBook Pro). I have to say, not the easiest job. Two key areas that are a headache:

  1. refitting the tension spring to the back of the CPU.
  2. Refitting the screen (mainly because it was my first attempt). However, I have to say, the machine fired back up first time, absolutely no issues. Key point - The fusion drive, for obvious reasons, splits. Again a noob to this, but actually wasn’t so hard to fix. I’m an OCD kinda guy and hated having a separate SSD & PCIe drive. I want the OS to run from the blade and the crap loaded onto the SSD. Easy process. Boot from your previously cloned externally HDD. Note - the clone on this drive automatically splits into two volumes when it copied my original fusion drive. Go into recovery mode at boot up. Takes a few minutes to boot. Run terminal from the utilities menu and the “diskutil resetFusion”. Reboot the machine from your external drive and clone back onto your newly built fusion drive. You can rebuild a fusion drive with SSD & PCIe. Job done. I have to say, the machine is running well. Geekbench scores are pretty much inline with average scores for this new spec. Update (05/15/2020) Key point - The fusion drive, for obvious reasons, splits. Again a noob to this, but actually wasn’t so hard to fix. I’m an OCD kinda guy and hated having a separate SSD & PCIe drive. I want the OS to run from the blade and the crap loaded onto the SSD. Easy process. Boot from your previously cloned externally HDD. Note - the clone on this drive automatically splits into two volumes when it copied my original fusion drive. Go into recovery mode at boot up. Takes a few minutes to boot. Run terminal from the utilities menu and the “diskutil resetFusion”. Reboot the machine from your external drive and clone back onto your newly built fusion drive. You can rebuild a fusion drive with SSD & PCIe. Job done. I have to say, the machine is running well. Geekbench scores are pretty much inline with average scores for this new spec.

Confirmed today, I took apart my 2019 iMac base 6 core 8500. Upgraded to Samsung 970 EVO Plus 1TB - No Issue with the Latest firmware 2B2QEXM7 released on 2019/5/20. Upgraded to 12TB Seagate EXOS HDD - Have hdd fan speed issue, did not put the OWC sensor. Use Mac Fan Control as alternative solution. Upgraded Ram Kingston KHX2666C15S4/16G - No Issue. The CPU is changeable, not soldered - Not upgraded yet, I’m okay with 8500’s performance so far. But I’m sure the CPU is upgradeable. Update (06/24/2019) Upgrade is fine, but the photos in https://www.instagram.com/p/BzF7bNoIreS/ seems has thermal sensor for the HDD. BTW, Zach, what is your normal idle fan speed after upgraded to 8TB HDD? Mine idle speed is about 1600-1700rpm, the fan sound is very noticeable. The lowest fan speed is 1200rpm, and the highest fan speed is 2593rpm from the Mac Fan Control settings. Thanks

Hi everyone, I did the core I5 3.0ghz cpu upgrade with Intel I9-9900K and everything went fine. I only recommend to take out ram Dimm before doing anything, and of course put the ram back inside after iMac reassembling.

Hi, I have just done the upgrade from iMac 27 2019, i5 8500k to i9 9900kf.  You must be very careful changing the cpu, it’s easy to damage the pins under the cpu. Puting back the cooler is the hardest part of the surgery. Also no heat problem or full speed running fan. Everything’s running smooth for now.   I also install Samsung 980 pro with the hope that it runs at full speed, but there is no benefit at all. Because it’s not running at full speed. You don’t get more than 3000 write and read speed because of Pcie 3.0 x4.  So I put back my Samsung 970 evo and happy with it for now.