I have a late 2012 27" iMac with the fusion drive set up, 128ssd and 1T drive. Mac OS is High Sierra version 10.13.3. Recently my Mac locked up and wouldn't shutdown or boot up ( eventually pulled power chord.) Had an appointment with Genius Bar and they were able to get the OS on the ssd and iMac working. But they said the internal hard drive is probably bad. Can an external usb ssd take the place of the bad internal drive without opening the iMack up? Would installing programs and games on the usb drive work, mouse and keyboard within the programs. I'm not totally blank about the way the Mac works but far from an expert. Thanks.
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External USB drive replacing internal drive.
- Thread starter rsba1
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Yes that would work or you could even get an authorised Apple service centre to replace you internal hdd th an ssd and redo the fusion with all ssd.
You can even create an all ssd fusion with an external drive. Here is a guide.
IF the internal 128gb SSD portion of the fusion drive still works -- even if the 1tb HDD portion has failed -- you should still be able to boot and run the iMac using the internal SSD in "de-fused" mode.
Is this what the genius bar guy did for you?
If it's up-and-running that way, and you don't want to break it open, you could just plug in a USB3 external drive for additional storage.
The drive could be either an HDD or SSD, your choice.
The 128gb internal SSD will be a little faster than an "external booter".
It's also "large enough" to run the iMac without problems, SO LONG AS you keep large libraries of things (movies, music, pictures) on the external drive.
If I was in your situation, the above is what I'd do.
The iMac is approaching 6 years old now.
You could probably squeeze 2, 3 or even 4 more years out of this way.
Is this what the genius bar guy did for you?
If it's up-and-running that way, and you don't want to break it open, you could just plug in a USB3 external drive for additional storage.
The drive could be either an HDD or SSD, your choice.
The 128gb internal SSD will be a little faster than an "external booter".
It's also "large enough" to run the iMac without problems, SO LONG AS you keep large libraries of things (movies, music, pictures) on the external drive.
If I was in your situation, the above is what I'd do.
The iMac is approaching 6 years old now.
You could probably squeeze 2, 3 or even 4 more years out of this way.
I guess thats what he did because I can run the iMac via the internal SSD. Confused on the de-fusing of the tb HDD. How would one fuse the SSD with an external drive? Thanks
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Thanks for the reply, but the "guide" didn't show up in your response.
There are many guides. Here is one:-
https://medium.com/@dalemugford/diy-fusion-drives-the-right-way-2c9baa368984
https://medium.com/@dalemugford/diy-fusion-drives-the-right-way-2c9baa368984
OP wrote:
"I guess thats what he did because I can run the iMac via the internal SSD. Confused on the de-fusing of the tb HDD. How would one fuse the SSD with an external drive?"
Try this and report back here with the results:
1. Boot to the finder. You want to see the internal drive icon on the desktop
2. Click ONE TIME on the drive icon to select it
3. Type "command-i" (eye) to bring up get info
4. Check "capacity".
5. Tell us what the report is.
If it's 128gb +/-, sounds like you're booting from a "de-fused" internal SSD.
If that's the case, my advice is:
LEAVE THINGS ALONE INSIDE.
The internal SSD will run "standalone" much faster than it would run if "fused to" another drive.
I suggest you download "BlackMagic Speed Test" (free), then run it.
Post your read/write results here for all to see. We'll let you know how you're doing.
I realize 128gb probably "isn't enough".
In that case, add EXTERNAL USB3 storage.
It could be an SSD or an HDD. Doesn't really matter.
DO NOT "fuse" this to the internal drive -- just let it exist as a second external drive.
You'll have TWO drive icons on the desktop.
It's no big deal to "manage files" between them.
You'll know where things go and where things are.
As far as the dead internal HDD is concerned:
JUST LET IT BE -- dead and buried.
So long as it doesn't "muck up" anything else -- leave it alone.
The iMac will run better without it!
"I guess thats what he did because I can run the iMac via the internal SSD. Confused on the de-fusing of the tb HDD. How would one fuse the SSD with an external drive?"
Try this and report back here with the results:
1. Boot to the finder. You want to see the internal drive icon on the desktop
2. Click ONE TIME on the drive icon to select it
3. Type "command-i" (eye) to bring up get info
4. Check "capacity".
5. Tell us what the report is.
If it's 128gb +/-, sounds like you're booting from a "de-fused" internal SSD.
If that's the case, my advice is:
LEAVE THINGS ALONE INSIDE.
The internal SSD will run "standalone" much faster than it would run if "fused to" another drive.
I suggest you download "BlackMagic Speed Test" (free), then run it.
Post your read/write results here for all to see. We'll let you know how you're doing.
I realize 128gb probably "isn't enough".
In that case, add EXTERNAL USB3 storage.
It could be an SSD or an HDD. Doesn't really matter.
DO NOT "fuse" this to the internal drive -- just let it exist as a second external drive.
You'll have TWO drive icons on the desktop.
It's no big deal to "manage files" between them.
You'll know where things go and where things are.
As far as the dead internal HDD is concerned:
JUST LET IT BE -- dead and buried.
So long as it doesn't "muck up" anything else -- leave it alone.
The iMac will run better without it!
It is running de-fused and reports total capacity of 121 gb flash storage with 99.7 gb available. When I try to run Black Magic it says the drive is read only. Don't see how that can be with the operating system and all on it. I also added a Seagate 1TB slim+ usb 3.0 drive and BM says the same thing that it is read only.
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Figured out how to set read-write option on drive and BM worked on the Seagate usb drive and gave about 110MB/ sec write and 140MB/sec read. Tried to reset the SSD to read-write and was told I didn't have permission to do that.
See these tips & links for booting from an external drive:
http://www.mpainesyd.com/filechute/BOOT_OSX_SSD.pdf
http://www.mpainesyd.com/filechute/BOOT_OSX_SSD.pdf
OP:
If BlackMagic won't run (I've seen the same error msg), you would need to boot from ANOTHER drive and then run it that way. But... don't worry about this, it's not really important.
What IS important is that you ARE booting from the internal SSD and it's working ok.
As I mentioned above -- what you need to do is FORGET ABOUT the dead internal HDD.
Add USB3 -external storage-.
It can be HDD or SSD -- your choice.
I'd AVOID both Seagate and WD "pre-assembled" drives.
If your needs aren't "too great", an SSD would do fine.
If BlackMagic won't run (I've seen the same error msg), you would need to boot from ANOTHER drive and then run it that way. But... don't worry about this, it's not really important.
What IS important is that you ARE booting from the internal SSD and it's working ok.
As I mentioned above -- what you need to do is FORGET ABOUT the dead internal HDD.
Add USB3 -external storage-.
It can be HDD or SSD -- your choice.
I'd AVOID both Seagate and WD "pre-assembled" drives.
If your needs aren't "too great", an SSD would do fine.
Makes sense. But only problem may be one I used to have in a Mac Mini Server (2 internal SATA drives). One died and whilst the other (boot) drove worked ok, OSX during boot up and accessing system report it would takes ages. I think it’s due to SATA controller having problems trying to interrogate the duff drive. Anyway I had to take out the dead one then it was fine. But it did work ok once booted up.
Thanks for the info, but the boot up is still quick,15-20 sec..
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Thanks, so far everything seems to be running fine.
Great! And as long as your mac supports USB3 or TB then external HDD / SSD for storage will generally be limited by the speed of the drive you’re using not the interface.