The SSD within my Late 2015 27" iMac 27" has died. Has anyone replaced the SSD and if so what drive (brand/model) did you buy? Not fusion drive or hard drive as I am told they have a replacement path, but an iMac with a SSD has a different type of connector that creates a problem or so I am told by OWC support.
iMac 27″, OS X 10.11
or so I am told by OWC support.
I just checked their site. It has the same info.
Given your computer is close to a decade old and considering the expense and trouble of a new internal SSD, you could consider the USB3 SSD external boot option. An SATA-6 SSD in a USB-3 enclosure will transfer data at a rate of about 400MB/sec, slower than your current internal but far faster than internal mech hard drives that can seldom surpass 150MB/sec transfer rates. It is usually fast enough that the user does not feel they are in "limp home" mode.
A good user tip is here:
Use an external SSD as your startup disk … - Apple Community
The tip's author typically would only recommend only drives sold in the Apple Store, but other will work just as well. For reliability I prefer an external USB3 enclosure that is self-powered (has an independent power brick), not powered only by the computer's USB bus like so may "budget-priced" external drives.
The slowdown may not even be perceptible in actual use. I have the fast factory SSD running at 2100-2700MBsec in my 2017 iMac 5K, and an aftermarket 500MB/sec SATA-6 drive on my older Macbook Pro. In actual use, both delivery more than acceptable speed and feel very much the same.
The external SSD is a viable and cost-effective option:
GGHulse wrote:
As a stop-gab before getting your reply, I attached a Sandisk Extreme SSD and was able to boot from it, but I can't upgrade the OS past Sierra (the default is El Capitan). I keep getting the error it can't create the partition. Now what is really strange, I have a WD My Passport external hard drive that I was able to upgrade the OS from El Capitan to Monterey (the last version for this machine) to the iMac prior to trying the external SSD.
I tried using Disk Utility to clone from the WD to the Sandisk SSD, but the restore also blows out that it can't create the partition on the SSD no matter if the SSD is formatted APFS, MAC OS Extended Journalled, et al. I have also selected Scheme of Master Boot Record, but no joy.
True it is an old machine, but still good enough for minor tasks.
I have a 2015 iMac (Retina 4K, 21.5-inch, Late 2015). It originally had a mechanical drive that was just too slow for running a MacOS that utilizes APFS. I took it to an Apple Authorized Service Provider several years ago and they installed a new internal 1 TB SSD, Samsung SSD 870 EVO 1TB SATA. It gets 510 MB/s, and is running Monterey, the latest MacOS for this Mac. This was a relatively inexpensive job, the SSD was about $100 (this was back in 2022) and the labor to install was $49, and because the AASP did the work, they returned it to me running Monterey and on first boot up it came up as a "new" computer, "hello," etc. and I simply used Setup Assistant to migrate everything from the backup. I have updated the MacOS several times and it all works as expected.
I did this back in 2022, nearly 3 years ago. Now of course a 2015 iMac is nearly 10 years old, so I'm not sure I would recommend it since you are stuck on Monterey with that model. That said, my 2015 iMac has been running great since its "refurbishment." Its Thunderbolt 2 ports are mostly useless, they are too old for modern drives, but it has plenty of fast USB 3 ports, and an ethernet port as well plus a card reader.
After formatting the external Sandisk Extreme SSD on another Mac, I booted into recovery and selected reinstall the OS. Unfortunately you do not get to choose which version and it installed El Capitan.
What I have been able to find out since is my Mac came with an SSD and there isn't a replacement path. If you had a fusion drive or a hard drive then you can get a replacement.
You can look for the ifixit guide for your Mac to see what you can do with your Mac type
I have built a samsung evo ssd in one of my older Macs
Follow Jack-19's user tip at > Use an external SSD as your startup disk … - Apple Community
As a stop-gab before getting your reply, I attached a Sandisk Extreme SSD and was able to boot from it, but I can't upgrade the OS past Sierra (the default is El Capitan). I keep getting the error it can't create the partition. Now what is really strange, I have a WD My Passport external hard drive that I was able to upgrade the OS from El Capitan to Monterey (the last version for this machine) to the iMac prior to trying the external SSD.
I tried using Disk Utility to clone from the WD to the Sandisk SSD, but the restore also blows out that it can't create the partition on the SSD no matter if the SSD is formatted APFS, MAC OS Extended Journalled, et al. I have also selected Scheme of Master Boot Record, but no joy.
True it is an old machine, but still good enough for minor tasks.
As a stop-gab before getting your reply, I attached a Sandisk Extreme SSD and was able to boot from it, but I can't upgrade the OS past Sierra (the default is El Capitan). I keep getting the error it can't create the partition. Now what is really strange, I have a WD My Passport external hard drive that I was able to upgrade the OS from El Capitan to Monterey (the last version for this machine) to the iMac prior to trying the external SSD.
I tried using Disk Utility to clone from the WD to the Sandisk SSD, but the restore also blows out that it can't create the partition on the SSD no matter if the SSD is formatted APFS, MAC OS Extended Journalled, et al. I have also selected Scheme of Master Boot Record, but no joy.
True it is an old machine, but still good enough for minor tasks.
Interesting - my 27” late 2015 iMac 5k retina also had a SSD failure the same day as you!
tried getting the boot image onto an external sandisk extreme however it fails to authenticate which version I need once the process starts.
how did you go about getting the boot drive onto the sandisk?
First format with another Mac the external SSD per the directions form others in this thread. Then boot the iMac into Recovery mode (you can also format the SSD here with the Disk Utility). Select restore OS from the Recovery screen. Unfortunately, it will install El Capitan. For the SSD, I cannot upgrade past Sierra. If there is something left of the original SSD< you might be able to upgrade past Sierra, which I was able to do with the WD hard drive I used before the SSD.
Follow up to your question, before trying to create a new boot disk on an external SSD, I did create one on an external hard drive. Yesterday I was able to copy the hard drive to the SSD using Carbon Copy Cloner. The trial version is fully operational for 30 days and there is a good video on YouTube on how to do this:
[Edited by Moderator]
+1 on Allan’s very wise advice!
The scheme must be GUID Partition Map.
The format must be Mac OS Extended (Journaled) for Sierra and older or... APFS for High Sierra and newer.
Some older Macs that can run High Sierra will not understand APFS & will need Mac OS Extended (Journaled).
True...
The point, was to inform the OP that they needed to change the Scheme from Master Boot Record to GUID Partition Map.
Ah.:)
Replacement SSD Late 2015 iMac
