Late 2015 27" 5K finally died after updating OSX, suggestions for external SSD?

[MasturB]

I hadn't used my iMac in maybe 5 years. Been using my 2012 MBP everywhere (put extra ram and internal SSD inside but physically it's just falling apart).

Recently dusted it and turned it back on. It was running very slow. Bought 32gb of RAM and it started working much much better, and upgraded it to newest possible OSX compatible and it worked great for a few days.

Yesterday was getting startup error. Internal HDD finally died, so the resurrection lasted than 2 weeks.

Any suggestions for external SSD + enclosure? Not sure if I feel like opening up this iMac and installing it inside. I also recently bought a brand new M4 MBP, but I liked having the iMac on my desk to do school work and such and MBP to bring around everywhere else. If it's less of a headache, would rather just run and use an external SSD for it.

 

[Barnclos]

I have a late 2015 27” that I used to dual boot - Monterey from the internal SSD, Sonoma (with OCLP) from a Samsung T7. I never had a moment when I thought that the T7 was a constraint - running usual office stuff, FCPX and Photoshop. I now have Sequoia on the internal SSD after I updated it by mistake 🤦🏼‍♂️.

There’s a Samsung T9 now, but I’ve read that it’s doesn’t reach its maximum speed on Macs, so may not be worth extra cost.

If you want to really push the boat out, there are new Thunderbolt 1/2 NVME enclosures starting to appear on eBay (late 2015 iMacs are Thunderbolt 2). They didn’t exist when I was using an external boot drive: back then, an NVME enclosure required an adapter connected to a powered hub connected to the enclosure. I haven’t tried a new enclosure, but I’m tempted.

 

[Fishrrman]

One of these will do you well:

Crucial X9 1TB Portable SSD, Up to 1050MB/s, USB 3.2 USB-C, External Solid State Drive, Compatible with Windows, Mac, & Android, Reliable Storage for Games, Files, & Backups, Black - CT1000X9SSD902

The Crucial X9 1TB Portable SSD (CT1000X9SSD902) provides high-performance storage with read speeds of up to 1050MB/s, allowing for quick and efficient transfers of large files, including high-resolution photos, 4K videos, and gaming data. With its 1TB storage capacity, this external SSD is perfe...

www.amazon.com

When the time comes, just "move it on over" to the new Mac.
It's USB3.1 gen2 (10gbps), but will run at USB3 speeds (5gbps) when connected to the 2015.
But when you connect it to a newer Mac that now supports USB4, those speed will double ...

 

[MasturB]

One of these will do you well:

Crucial X9 1TB Portable SSD, Up to 1050MB/s, USB 3.2 USB-C, External Solid State Drive, Compatible with Windows, Mac, & Android, Reliable Storage for Games, Files, & Backups, Black - CT1000X9SSD902

The Crucial X9 1TB Portable SSD (CT1000X9SSD902) provides high-performance storage with read speeds of up to 1050MB/s, allowing for quick and efficient transfers of large files, including high-resolution photos, 4K videos, and gaming data. With its 1TB storage capacity, this external SSD is perfe...

www.amazon.com

When the time comes, just "move it on over" to the new Mac.
It's USB3.1 gen2 (10gbps), but will run at USB3 speeds (5gbps) when connected to the 2015.
But when you connect it to a newer Mac that now supports USB4, those speed will double ...

So since the internal HDD is dead, should I just use this as the startup and storage?

I don't plan on using this Mac for maybe another 2 years max when I move. And even then I use my MacBook more than anything else. I am not doing anything complex other than photoshopping once in a while. But mainly just excel, word, browsing for schoolwork.

 

[Fishrrman]

"So since the internal HDD is dead, should I just use this as the startup and storage?"

Yes.
If the failed internal drive was a platter-based HDD, you'll notice a definite increase in speeds.

Do you have a backup of any kind?

 

[MasturB]

"So since the internal HDD is dead, should I just use this as the startup and storage?"

Yes.
If the failed internal drive was a platter-based HDD, you'll notice a definite increase in speeds.

Do you have a backup of any kind?

I don't technically have a backup. But i did have a backup of all the multimedia stuff. And since I've used my MacBook more the last 6 years that has all the recent stuff. Probably will back that up.

I'd essentially be starting from scratch.

I did a safe mode startup and disk utility. So the partitioned part appears to be fine that has the OS on it?

So if I get this external SSD, I'm essentially starting from scratch

 

[marius_3d]

you can use any SSD with USB3 interface, the speeds are around 400Mbps, more than HDD that was inside.

 

[MasturB]

"So since the internal HDD is dead, should I just use this as the startup and storage?"

Yes.
If the failed internal drive was a platter-based HDD, you'll notice a definite increase in speeds.

Do you have a backup of any kind?

Hey. So I got the SSD.

Installed the old OS X on it through safe mode/internet. (Currently OS X El Capitan)

Tried to install OS Monterey because it's the last OS that's compatible with my Late 2015 27" iMac, but I got this error message.

Any help?

 

[Fishrrman]

OP wrote:
"Installed the old OS X on it through safe mode/internet. (Currently OS X El Capitan)"
... and is now receiving error msg (as posted above)...

May I ask what you mean (exactly) by "safe mode/internet" ?

There is booting into safe mode (boot and hold down shift key continuously),
and...
There is booting into "internet recovery" (command-OPTION-R) at boot.

Which did you use?

Can you get booted into regular internet recovery?
- power off, all the way off
- hold down command+option+R and do not let go
- while still holding these keys, press and release the power on button
- keep holding those keys down!
- you can let go when:
a. you're asked for a wifi password (connecting via wifi)
or
b. you see the spinning globe on the screen.
- the utilities take a while to load, be patient

IF you can get to internet recovery...
- open disk utility
- IMPORTANT - go to the "view" menu and choose "show all devices"
- now look at the "list on the left".
- the topmost item should be the physical drive inside
WE ARE GOING TO ERASE IT COMPLETELY
- click on the drive one time to select it and click erase
- erase to APFS, GUID partition format
- now, quit disk utility and open the OS installer.

What version of the OS does it offer you?
It should offer Monterey.
Does it proceed, or does it give you the error that you posted above in reply 8?

If you DON'T see the error msg, give it a try this way and see what happens...

IMPORTANT:
I have read posts from others that somewhere (may have been around High Sierra or Big Sur) there was a kind of "incremental" firmware update, without which upgrades to later versions of the OS would fail. My recollection here is vague. If others are reading who have experienced this, could you help...?

 

[marius_3d]

you need to format the external SSD using Disk Utility, select 'AFPS".

maybe skip Monterey and install Sequoia with OCLP https://github.com/dortania/OpenCore-Legacy-Patcher/releases

 

[MasturB]

OP wrote:
"Installed the old OS X on it through safe mode/internet. (Currently OS X El Capitan)"
... and is now receiving error msg (as posted above)...

May I ask what you mean (exactly) by "safe mode/internet" ?

There is booting into safe mode (boot and hold down shift key continuously),
and...
There is booting into "internet recovery" (command-OPTION-R) at boot.

Which did you use?

Can you get booted into regular internet recovery?
- power off, all the way off
- hold down command+option+R and do not let go
- while still holding these keys, press and release the power on button
- keep holding those keys down!
- you can let go when:
a. you're asked for a wifi password (connecting via wifi)
or
b. you see the spinning globe on the screen.
- the utilities take a while to load, be patient

IF you can get to internet recovery...
- open disk utility
- IMPORTANT - go to the "view" menu and choose "show all devices"
- now look at the "list on the left".
- the topmost item should be the physical drive inside
WE ARE GOING TO ERASE IT COMPLETELY
- click on the drive one time to select it and click erase
- erase to APFS, GUID partition format
- now, quit disk utility and open the OS installer.

What version of the OS does it offer you?
It should offer Monterey.
Does it proceed, or does it give you the error that you posted above in reply 8?

If you DON'T see the error msg, give it a try this way and see what happens...

IMPORTANT:
I have read posts from others that somewhere (may have been around High Sierra or Big Sur) there was a kind of "incremental" firmware update, without which upgrades to later versions of the OS would fail. My recollection here is vague. If others are reading who have experienced this, could you help...?

Thanks for clarification.

I held down command+r (not option) and it went in to internery recovery mode. I did disk utility and formatted it first then did the OS X reinstall option.

 

[Fishrrman]

"I held down command+r (not option)"

That IS NOT "internet recovery mode".
All you did with command+R is boot to the internal recovery partition.

Internet recovery is:
Command-OPTION-R.

Print out my reply 9 to you above.
Then... follow it exactly, step by step.
Are the results the same?

 

[MasturB]

"I held down command+r (not option)"

That IS NOT "internet recovery mode".
All you did with command+R is boot to the internal recovery partition.

Internet recovery is:
Command-OPTION-R.

Print out my reply 9 to you above.
Then... follow it exactly, step by step.
Are the results the same?

Thanks. I'll try it later tonight.

 

[MasturB]

Error message I got when I hit erase for the internal drive.

 

[MasturB]

It did ask if I wanted to install Monterey but got this again.

 

[MasturB]

This is what disk utility view all shows

 

[Mactech20]

Erase the Crucial Startup disk as APFS. Are you able to install now? What OS did you originally have on the iMac?

 

[Fishrrman]

RE reply 14 above (error msg when trying to erase internal drive):

I realize this sounds illogical, but...
a. Get back into internet recovery
b. Open disk utility and select the internal drive
c. Try to erase it... BUT... try to erase to a PC format such as exFAT
d. Does this erase "go through" without problems?
e. If so, now try a SECOND ERASE, this time to APFS.

Sometimes this works on external drives. The idea is to "obliterate" any traces of the Mac OS and file system. After which, disk utility can succeed in re-formatting to Mac (whereas it had become tripped up before). It -might- work on the internal SSD. Or perhaps not.
But still worth trying.

 

[MasturB]

RE reply 14 above (error msg when trying to erase internal drive):

I realize this sounds illogical, but...
a. Get back into internet recovery
b. Open disk utility and select the internal drive
c. Try to erase it... BUT... try to erase to a PC format such as exFAT
d. Does this erase "go through" without problems?
e. If so, now try a SECOND ERASE, this time to APFS.

Sometimes this works on external drives. The idea is to "obliterate" any traces of the Mac OS and file system. After which, disk utility can succeed in re-formatting to Mac (whereas it had become tripped up before). It -might- work on the internal SSD. Or perhaps not.
But still worth trying.

Tried exFAT still failed.

 

[MasturB]

Erase the Crucial Startup disk as APFS. Are you able to install now? What OS did you originally have on the iMac?

El Capitan was on it originally I believe? Ok i did this. Now it's installing Monterey on external SSD. 1 hourish remaining.

 

[MasturB]

I can't seem to get it to finish installing.

Every time it is "installing" the progress bar gets down to an hour left. Then switches back to the apple logo startup (no startup sound). Then the startup progress bar goes on and then it goes back to to this screen. The offline recovery mode.

 

[MasturB]

Going to reinstall only asks me to reinstall El Capitan that I guess is from the partitioned part of the old internal drive.

Shut down and turned it back on again. Startup sound comes on but now it just stops at the Apple logo. No progress bar either for startup. Just seems to be a deadend.

 

[MasturB]

Another update. When restarting the computer, it now goes to internal recovery by default now without me holding keys on keyboard.

 

[MasturB]

I am currently on my 2012 MBP (with a replaced internal SSD I've had for years now, and added ram).

It's currently on Catalina 10.15.7. Crazy how this is running better still even though physically falling apart, than the iMac.

So is it looking like I'm just gonna have to replace the internal drive to get this to work for the iMac? Doesn't seem to want to cooperate with the external SSD.

I went in to internal recovery mode, tried to reformat the external SSD but when I tried to do Mac OS-Journaled it kept failing. So I had to go in to internet recovery disk utility to do it again to journaled, now I'm back on Internal Recovery re-installing El Capitan again.

Open to any suggestions, otherwise I'll just try to update it manually again once El Capitan finishes. I shoul be able to try and install Sierra, High Sierra, or anything before Monterey right?

Welp. Tried to do Migration Assistant to move over my MBP 2012 data to the iMac but couldn't since the OS is newer on the MBP than the iMac.

Should I just backup this MBP 2012 data running on Catalina to the SSD, then try to restore it in recovery mode on this iMac? I also have an external HDD as well. Probably should back up this MBP in Time Machine anyways to that HDD now just incase.

 

[MasturB]

RE reply 14 above (error msg when trying to erase internal drive): I realize this sounds illogical, but... a. Get back into internet recovery b. Open disk utility and select the internal drive c. Try to erase it... BUT... try to erase to a PC format such as exFAT d. Does this erase "go through" without problems? e. If so, now try a SECOND ERASE, this time to APFS. Sometimes this works on external drives. The idea is to "obliterate" any traces of the Mac OS and file system. After which, disk utility can succeed in re-formatting to Mac (whereas it had become tripped up before). It -might- work on the internal SSD. Or perhaps not. But still worth trying.

RE reply 14 above (error msg when trying to erase internal drive): I realize this sounds illogical, but... a. Get back into internet recovery b. Open disk utility and select the internal drive c. Try to erase it... BUT... try to erase to a PC format such as exFAT d. Does this erase "go through" without problems? e. If so, now try a SECOND ERASE, this time to APFS. Sometimes this works on external drives. The idea is to "obliterate" any traces of the Mac OS and file system. After which, disk utility can succeed in re-formatting to Mac (whereas it had become tripped up before). It -might- work on the internal SSD. Or perhaps not. But still worth trying.

Just bumping to see if you saw my other replies.