I have a late 2014 27” iMac and I need to install a new ssd, the original HD gave up but I managed to install Mojave but it doesn’t have Fusion Drive, when I put in a new ssd drive how do I switch on the Fusion Drive, am I right in thinking that it is a separate ssd, if that’s faulty how do I find out
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How do I install a Fusion Drive
- Thread starter thewall
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A Fusion Drive is a software effect to make two separate devices behave like one drive. Those iMacs came with one tiny SSD, to provide a faster speed, and a mechanical hard drive for larger storage. If you're replacing the hard drive with an SSD, then don't make a Fusion drive. Just use the SSD as a single drive.
There's no benefit to making a Fusion Drive from two SSDs -- given that the original SSD is tiny: 120 Gb at best.
Remember that if one part of a Fusion drive fails, the whole thing is bricked, with no recovery: you'll have to erase and restore from your backup.
There's no benefit to making a Fusion Drive from two SSDs -- given that the original SSD is tiny: 120 Gb at best.
Remember that if one part of a Fusion drive fails, the whole thing is bricked, with no recovery: you'll have to erase and restore from your backup.
Question:
"How do I install a fusion drive"
Answer:
You DON'T.
Not in these times. Not any more.
If you have replaced the old platter-based drive with an SSD...
and...
If you now have Mojave up-and-running from the new SSD...
then...
Just leave it that way.
You can install a copy of the OS onto the original SSD portion of the fusion drive, but just let it remain "a standalone SSD" in addition to the new one.
If it was me...
I'd get both drives running again as "standalone" drives...
and then...
I'd do a speedtest on both to see which is fastest...
and then...
If the original SSD is noticeably faster, AND if it's a 128gb SSD that was used in some fusion drives...
then...
I might consider setting that to be the boot drive, while keeping things "slimmed down" on it so as not to fill it up more than about 50-60%.
I would do that by moving large libraries of stuff (photos, music, movies) to the new SSD, thus keeping the home folder "lean and clean".
"How do I install a fusion drive"
Answer:
You DON'T.
Not in these times. Not any more.
If you have replaced the old platter-based drive with an SSD...
and...
If you now have Mojave up-and-running from the new SSD...
then...
Just leave it that way.
You can install a copy of the OS onto the original SSD portion of the fusion drive, but just let it remain "a standalone SSD" in addition to the new one.
If it was me...
I'd get both drives running again as "standalone" drives...
and then...
I'd do a speedtest on both to see which is fastest...
and then...
If the original SSD is noticeably faster, AND if it's a 128gb SSD that was used in some fusion drives...
then...
I might consider setting that to be the boot drive, while keeping things "slimmed down" on it so as not to fill it up more than about 50-60%.
I would do that by moving large libraries of stuff (photos, music, movies) to the new SSD, thus keeping the home folder "lean and clean".
Last edited:
Thanks Fishrrman the reason I’m replacing the original HD is that I had the “flashing ?” But managed to get it up and running and installed Mojave tried Big Sur which it was running before but it would not install it ,I’ve had it running on Big Sur on an external ssd but the Mac wouldn’t go to sleep,restart or shutdown I had to do it manually.
So if I can get it to run after I’ve installed the ssd I will be happy
Would the Fusion Drive ssd failed as the Mac is running perfectly at the moment
So if I can get it to run after I’ve installed the ssd I will be happy
Would the Fusion Drive ssd failed as the Mac is running perfectly at the moment