Upgrade Fusion Drive?

[Jay7676]

Are there any up to date guides to upgrade the fusion drive?

I have a late 2015 imac and with each iteration of MacOS the drive is getting slower.

I have the 1TB fusion drive, is it possible to replace entire drive? I believe its made up of 2 parts, the ssd and mechanical drive.

Or will I have to keep the SSD bit and just upgrade the mechanical drive? Happy to use whatever I need to do it.

I would prefer to keep my data. I have a time machine backup, not sure if that helps.

Thanks for any advice

 

[macguru9999]

yes, you can just replace the spinner with an ssd and ignore the tiny ssd in there on the mobo. Personally, I have saved an apple ahci 1tb ssd to put on the mobo and ill put a large sata ssd in as well to replace the spinner.

 

[Fishrrman]

You can "split" the fusion drive, then replace the HDD with an SSD.
The small factory-installed SSD can be left "in place" and not used if you wish.

BE AWARE that when you split a fusion drive, ALL THE DATA IS LOST, so you must have a known good backup from which to restore.
If it was me, I'd create a bootable cloned backup using either CarbonCopyCloner or SuperDuper.

Another option would be to find a compatible blade SSD (probably from Apple) and replace the SSD. BE AWARE that Apple uses a proprietary connector, so I'm pretty sure you need either an Apple-brand replacement or the "proper adapter" (if such an adapter is even available).

Opening the iMac is not a trivial procedure and there's a significant danger of breaking something during the install. Are you sure of your abilities?

There's "another way":
Get an external USB3 SSD.
You can plug that into a USB3 port, and set it up to become the external boot drive.
Works quite well, and you will see read speeds around 420MBps.

 

[Jay7676]

Opening the iMac is not a trivial procedure and there's a significant danger of breaking something during the install. Are you sure of your abilities?

I repair mobile phones/microsolder and fix laptops so yes I don't think it will be an issue but then again, it is a Mac!

And thanks for all the advice, maybe an external drive would be a lot less hassle. I didn't realise you could boot from an external device.

So even if I left the internal fusion drive as is, I could install the OS on and external drive and run it all from there? Or even copy the current OS and files to the external drive and boot?

Sorry normally a PC person, this is my first Mac.

 

[Jay7676]

Have ordered a fast external SSD.

So its smaller than my current drive. My current drive has 256GB used, the new drive is 500GB.

If I use Carbon Copy Cloner will I be able to transfer the entire drive to the external and boot from it?

 

[Fishrrman]

"If I use Carbon Copy Cloner will I be able to transfer the entire drive to the external and boot from it?"

Yes.
This is as easy at it gets. So easy that even I can do it.

What version of the OS?

 

[Jay7676]

It is running Monterey

 

[Fishrrman]

"It is running Monterey"

Hmmmmm.....
In that case, it may be a little harder.

You must (absolutely must) use the most recent CCC beta.
You need to choose something called "legacy backup assistant" (or something named similar to that).

See if that works.

If it doesn't (assuming you have made the CCC backup)...
... Install a fresh copy of Monterey onto the SSD.
Then, begin the regular Mac setup (choose your language, etc.).
At the appropriate moment, setup assistant will ask if you wish to migrate data.
Now connect the CCC backup, and let setup assistant "digest" it.
I'd choose to migrate everything.
That will probably work.

 

[Jay7676]

Thanks for the info, ok stupid question how do I setup a fresh copy of Monterey onto the SSD?

For reference I have a late 2015 iMac 21.5

 

[Fishrrman]

I'd try the CCC "legacy bootable backup" first.

As for doing a fresh install onto the SSD, you'll have to re-download the Monterey installer.
Then, run it, but "aim it" at the SSD (instead of the internal drive).

 

[Jay7676]

Many thanks. New drive comes today so will give it a go and failing that will install to the external drive.

Can I use a time machine back to restore data to the new external drive? (if I have to do a fresh install)

 

[Jay7676]

Ok so CCC was a fail. At restart the Apple logo appeared and got half way across then restarted and after a couple of times said something about an error.

So I installed Monterey to the external SSD and all is good, migrated everything from the current OS and everything is working.

Its like night and day to what it was like before.

Something strange, on the fresh install all the icons in the dock were nice and crisp (non-retina display). But since migrating they are kind of blurry or soft, same issue I had before so I assume its some setting that has done it but no idea which.

 

[Fishrrman]

"Something strange, on the fresh install all the icons in the dock were nice and crisp (non-retina display). But since migrating they are kind of blurry or soft, same issue I had before so I assume its some setting that has done it but no idea which."

I suggest you visit this page and read ALL OF IT carefully:

How to Fix Blurry Fonts on macOS Mojave (With Subpixel Antialiasing)

Apple's macOS Mojave disables subpixel antialiasing, also known as font smoothing, by default.

www.howtogeek.com

I suggest you try ALL of the settings that are possible.
(I think the values are 0, 1, 2 and 3)
You need to log out and log back in each time you change the value.

The article was originally written for "Mojave", but I believe the same issues persist all the way to the present day OS...

 

[Jay7676]

Thanks for the link, will have a read through it

 

[ignatius345]

I repair mobile phones/microsolder and fix laptops so yes I don't think it will be an issue but then again, it is a Mac!

Last year I opened up my old 27" iMac 5K and replaced the platter-based part of my Fusion Drive with a SATA SSD. Bought a kit from I think iFixit, which came with all the tools and the adhesive strips to put the screen back on. Took about 2-3 hours total, and worked beautifully. I just went slowly and followed the instructions in the iFixit site. Dealing with the adhesive was horrible, but doable.

For data migration (this was under Catalina), all I did was put my new drive into an external USB enclosure temporarily, hook it up, clone my Fusion Drive to the new drive, boot off it to make sure it worked -- and then physically installed it into the machine. When all was said and done it was identical. I gather it's gotten a bit harder these days under Monterey and Big Sur.

I'd also throw out that Migration Assistant does a pretty damn good job of moving in user accounts, applications and settings. The "full clone" thing is good, but it's not the only way to go.