If I buy (2nd hand) a 2019 iMac with a "Fusion Drive", can I replace the Spinning Hard drive with an SSD ?

[rice7373]

There are a couple of videos online with people doing this, but will it cause any issues with the way the onboard flash recognises or communicates with the new SSD?
Does the SSD have to be a similar size as the HD that it replaces?
* An iMac from2019 is my budget maximum. But I have read so many negative reviews on the Fusion Drive. I have a spare 1TB SSD at home... and I really hope I can just replace the HD.
Any knowledgeable advice would be very appreciated. Thank you

 

[EbeyTech]

I would recommend checking out iFixit. They provide pro level guides and options to purchase the needed tools. https://www.ifixit.com/Guide/iMac+Intel+27-Inch+Retina+5K+Display+2019+Blade+SSD+Replacement/137596
I've used several of their guides for similar iMac HD/Blade to SSD replacements. I just followed the guides and every upgrade (I did 4 of them) were successful and the new drives worked perfectly. Hope this helps.

 

[Juicy Box]

You have options, and not all require opening your Mac.

You can "defuse" the Fusion Drive and replace the internal HDD with a SATA SSD.

You can use an external SSD and leave the Fusion Drive, use it as a bootable back up, extra storage, etc.

You can "defuse" the Fusion Drive, and just run on the SSD portion. If this 2019 iMac has the 1TB Fusion Drive, the SSD portion is only 32GB. Originally when the Fusion Drive was introduced, the Fusion Drives all had 128GB SSD. In 2015, the SSD size was reduced to 24GB for the 1TB sized Fusion Drive, and in 2017, they increased it to 32GB for the 1TB sized Fusion Drive.

You can create your own Fusion Drive using a few different possible combinations, 1. The internal SSD with your own SATA SSD. 2. Internal SSD with external drive. 3. Two external drives. Each has their own pros and cons.

 

[Juicy Box]

But I have read so many negative reviews on the Fusion Drive.

The Fusion Drives are not inherently bad, and was a really good balance of size, speed, and cost when they first launched in the fall of 2012.

In 2012, SSD prices were insane, so using a smaller SSD fused with a large, cheap HDD, enabled Mac users to get SSD speeds with HDD storage sizes, priced a little higher than just a straight HDD.

As SSD prices started to fall, the necessity of Fusion Drives started to fall as well.

Apple also hobbled the 1TB Fusion Drive in 2015 with the reduced SSD portion, and then again with APFS, as it is not optimized for HDDs compared to the older HFS.

The HDD performance decrease under APFS is the biggest reason for complaints of the Fusion Drive, imo.

There is also the heat and higher failure rate of Fusion Drives versus straight SSDs. Apple doesn't always provide the best cooling designs in their Macs, and this, plus general wear and tear, has lead to a lot of HDD portion failures of Fusion Drives.

 

[Fishrrman]

I would not buy any iMac that has a fusion drive in it.

Before you attempt this, are you absolutely certain of your abilities to open it up and do the job, without breaking something inside? Some folks THOUGHT they could do it, then pried it open, and then.... broke something.

If you want a 2019 iMac, then look for one that came with a factory-installed SSD.
They can be found.
Things will go MUCH easier that way.

Put the SSD you have into a USB3 enclosure and use it that way.


Some folks have mentioned an alternative:
Get the fusion drive, but get one with at least 2tb.
The 2tb version has an internal blade SSD of 128gb, and a platter-based HDD of 2tb.
Now... SPLIT the fusion drive into separate drives (easily done).
Then... Set up the 128gb SSD to be the boot drive, but keep it "lean and clean". Use the HDD for large libraries of stuff (movies, music, pictures).

IF you manage it this way, you'll have the benefits of a fast internal SSD (the Apple blades are quite fast), and you WON'T be prying it open.

Final thought:
Skip the iMac. Get a 2018 Mini instead. These ALL came with internal SSDs.

My opinion only.

 

[rpmurray]

Really would need to know how much you're paying for the 2nd hand iMac, and what the specs are.

If you can get it plus an SSD (to replace the HD) for less than what Apple charges for a similarly speced refurb then go for it. If this is your first time prying one of these open then you want to check OWC, iFixit, and Youtube for videos on how to do that and watch them 10 or 20 times until you're familiar with the whole process so you don't break anything.

If you're getting a Fusion drive then I'd go with an adapter and NVMe 1TB SSD drive to replace the blade already in the iMac and remove the HD. Will make it cooler running and if you need more storage you can get a Thunderbolt enclosure and put another NVMe into that and hook it up externally.

 

[unphased]

I just picked up a 1TB Fusion Drive sporting 27" 2019 iMac for $550. Wife still really likes this design and the 5K display admittedly is still, shall we say, legit.

I'll definitely need to be doing something about this terrible storage performance, I already have a thunderbolt only (and hence not terribly useful as a jump drive as i have no thunderbolt on my PCs) NVMe enclosure that will do the trick dedicated for this as a boot drive, so I've got little reason to risk opening the thing up, other than to make it look clean without a drive dangling off it.

I did the heatsink mod on my 12" 2017 macbook the other day, and that wasn't a walk in the park but it wasn't too challenging. However opening up these iMacs is no joke with all that adhesive in play... Yeah I'm not going to open this thing up. There may not be any reason to unfuse the storage either.

The other thing I noticed right away is the mouse cursor doesn't even move smoothly. It's going at like 30hz. Sigh. Very spoiled by my M1 Max MBP.

 

[AL2TEACH]

and I really hope I can just replace the HD.

That's what I had done but at a shop, lol. they replaced the spinner with a ssd and the flash (fusion) drive is there but not used. All is good.