My fusion drive on my 2019 iMac is dying, so I bought an external usb c 2 case, and an HP Drive 2TB SSD and installed it, I installed macOS on it and migrated my time machine backup over to it, and it seemed OK, however, somehow the computer restarted, and now refuses to boot from that external drive at all. Any hints on a suitable brand or replacement disk to use as a drive? I’m hesitant to do surgery on the iMac to replace the fusion drive with an internal SSD.
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Good SSD combo for external bootable drive for iMac?
- Thread starter kenfused
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I had the exact same problem with my 2015 iMac and solved it like THIS. Took some effort to get it to boot and completely run from an external ssd but I got it figured out (the this is a macrumours thread)
Yes if starting off the original Fusion Drive I can pick it
SSK Aluminum M.2 NVME SATA SSD Enclosure Adapter, USB 3.2 Gen 2 (10 Gbps) to NVME PCI-E SATA M-Key/(B+M) Key Solid State Drive External Enclosure Support UASP Trim for NVME/SATA SSDs 2242/2260/2280
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I set up my SSD just like you mentioned, but I’m wondering if it is some kind of hardware incompatibility that is giving me the problem now, it also gets pretty hot, so I’m wondering if there’s a thermal problem
Could be, my Qwiizlab M.2 NVMe and SATA External Enclosure with Leven JPS600 2TB ssd (both very cheap) does not get hot at all but the Leven ssd does have a heatsink on it and I added thermal padding. I have no problem updating or using the iMac/ssd but when I restart it does take a pretty long time and I do do anything heavy on it as I use my mini M2 for real work.
I have a lot of different NVME enclosures (14 or 15, I loan a few out, so not sure), and some NVME blades can get pretty hot during long file copies. Some of the blades will make the enclosures almost too hot to touch. But, that also means that the heat transfer, through the case, is working pretty good. That's how it works. Your SSK enclosure came with a thermal pad (usually a light blue or white). You need to make sure that is used, should be info in the data sheet that came with the enclosure.
I am using it, wondering if the HP blade is to blame. I think I may try an SATA SSD instead since those run cooler and I am limited by usb c anyway
I'm just wondering if there is some corruption on your boot drive that is preventing it from booting from it.... I just have a hard time believing that a hot ssd would be unable to boot.
It the iMac still bootable from its internal disk and if so I would go through the process of wiping the external ssd and creating a new bootable disk again. When you look at the thread of me doing it you will notice that it was a pretty intense process and I wiped and recreated the bootable disk multiple times before I got it to work properly. And as I said I used pretty cheap ingredients (enclosure and 2tb ssd for $105) so I would try a few times.
But of course I did use a 2015 27" iMac and you have a 2019 so I do not know if there could be an underlying issue with that.
Thanks... I could try the process again, but reluctant to spent 24 hrs installing OS and tranferring from Time Machine if the long term process may get corrupted again, or have errors… I’ll try with a different SATA SSD and enclosure and fingers crossed that works. What a bummer. It all seemed to work so well at first after the initial istallation
The heat is pretty normal. There can also be a lot of drive activity when you have first installed a new system.
If you really want to try a different drive, you can search for listing of nvme power efficiency (might be a good search term for that.
One of the NVME blades that is often near the top of the list for that power efficiency, is HK Hynix.
It is sold by one of the companies that actually makes the chips. I think you will find the prices to be on the low end, particularly for a well-rated blade such as this.
If you really want to try a different drive, you can search for listing of nvme power efficiency (might be a good search term for that.
One of the NVME blades that is often near the top of the list for that power efficiency, is HK Hynix.
SK hynix Gold P31 2TB PCIe NVMe Gen3 M.2 2280 Internal SSD, Up to 3500MB/S, Compact, Form Factor SSD - Internal Solid State Drive with 128-Layer NAND Flash
Experience the breakthrough upgrade from a global tech pioneer. SK hynix Gold P31 delivers the world’s first 128-layer NAND, fastest-in-class speed, easy data migration, and 5-year warranty. The latest innovation from the world’s second-largest memory maker, Gold P31 is designed to provide striki...
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So as I had already bought a new mini M2 I had time and I was not interested in spending a ton of money. So with that knowledge I would be very hesitant to spend money on a more expensive ssd and/or enclosure as mine runs completely fine from a combination that was $105 for 2TB.
Things to make sure are good are the actual boot disk... has it ever booted correctly and if so what changed before it broke.
Make sure the connector cable that you use between the ssd and the mac is good and in proper working order. Any time I now have some minor problem with booting up it is because the cable is not properly connecting.
But don't start buying more expensive stuff unless you understand what the problem is.
Some "Fishrrman stoopid questions™" ...
- If you boot while holding down the option key (keep holding it down!), does the external SSD show up in the startup manager?
- If it does, and you select it, do you get a good boot?
- Also, have you tried going to the startup disk preference pane, and selecting the external to be the boot drive...?
- If you boot while holding down the option key (keep holding it down!), does the external SSD show up in the startup manager?
- If it does, and you select it, do you get a good boot?
- Also, have you tried going to the startup disk preference pane, and selecting the external to be the boot drive...?
"did boot with it selected and it crashes partway thru"
Try booting again with a "safe boot" (hold down the shift key while booting).
If you can't resolve this problem, then...
I would "wipe" the SSD and start over.
Boot to INTERNET recovery
Command-OPTION-R
Keep holding down those keys for a while after you press the power on button!
If you use wifi, enter your wifi password when requested.
Once the utilities get loaded, open disk utility.
IMPORTANT IMPORTANT IMPORTANT
Go to the "view" menu and choose "show all devices"....
Now, look at the list on the left.
Locate the SSD.
There may be more than one "line" associated with it.
You want to click on the highest one that represents the drive itself
(and not a "volume" that is ON the drive)
Now, click "erase" (make sure any user data on the drive is BACKED UP).
Erase to APFS, GUID partition format.
When the erase is done, quit disk utility.
Now open the OS installer.
Start clicking through.
The Mac will reboot one or more times, and the screen will go dark for a minute or more with no other indication of activity. Just be patient.
When done, you should see the initial setup screen (choose your language).
At this point, if you have a backup, connect it.
Start clicking through.
It's UP TO YOU as to whether you want to restore from the backup, or create a completely-new account.
I'd try the backup first.
If you're going with setup assistant, it will ask if you wish to migrate from another drive - YES, you do.
"Point the way" for SA to the backup.
Give it time to "digest" everything. Be patient.
SA will present you with a list of stuff to migrate.
I'd try everything.
Let SA do its thing, again, will take a while.
When done, you should see your login screen.
Good luck.
Try booting again with a "safe boot" (hold down the shift key while booting).
If you can't resolve this problem, then...
I would "wipe" the SSD and start over.
Boot to INTERNET recovery
Command-OPTION-R
Keep holding down those keys for a while after you press the power on button!
If you use wifi, enter your wifi password when requested.
Once the utilities get loaded, open disk utility.
IMPORTANT IMPORTANT IMPORTANT
Go to the "view" menu and choose "show all devices"....
Now, look at the list on the left.
Locate the SSD.
There may be more than one "line" associated with it.
You want to click on the highest one that represents the drive itself
(and not a "volume" that is ON the drive)
Now, click "erase" (make sure any user data on the drive is BACKED UP).
Erase to APFS, GUID partition format.
When the erase is done, quit disk utility.
Now open the OS installer.
Start clicking through.
The Mac will reboot one or more times, and the screen will go dark for a minute or more with no other indication of activity. Just be patient.
When done, you should see the initial setup screen (choose your language).
At this point, if you have a backup, connect it.
Start clicking through.
It's UP TO YOU as to whether you want to restore from the backup, or create a completely-new account.
I'd try the backup first.
If you're going with setup assistant, it will ask if you wish to migrate from another drive - YES, you do.
"Point the way" for SA to the backup.
Give it time to "digest" everything. Be patient.
SA will present you with a list of stuff to migrate.
I'd try everything.
Let SA do its thing, again, will take a while.
When done, you should see your login screen.
Good luck.
Thank you... I decided to go with a different SSD. Using a Crucial 2TB MX500 SATA style SSD, in a different external enclosure. So far so good... I thought about reformatting the NVME SSD, but even to wipe it clean took so long, I was nervous about depending on it in the future. So far the Crucial drive is ok, even though I know the technology is slower than NVME. Still faster than my fusion though. Thanks everyone