If you have a 2019 model iMac or earlier with a “Fusion Drive” or “Hard-Disk-Drive”, we recommend replacing with an SSD ASAP as the drive could fail at any minute.
apple have been shipping iMacs with SSD (Solid-State-Drives) since 2020 due to the high failure rates of HDD (Hard-Disk-Drives) and Fusion drives in pre-2020 iMacs which were only 1 or 2 years old (and covered by AppleCare)
Q – But aren't Fusion drives the same as SSD's?
A – Yes and No. Fusion drives incorporate a small SSD in combination with a much larger (1TB, 2TB, 3TB) HDD (Hard-Disk-Drives). It is not the SSD component that is prone to failure but the HDD component is.
Q – How can I tell what kind of drive my iMac Has?
Depending on the mac OS, there are a few ways. What you are looking out for is if any of the drives are referred to as “HDD” or “Fusion Drives”
or Applications > Utilities > disk utility
The following is a Fusion Drive …it has a small 128GB SSD and a 1TB or bigger HDD
What you want to see in ONLY “SSD” and nothing else
If you see any “HDD” or “Fusion Drive” you know you have the mechanical HDD (Hard-Disk-Drive) that is prone to failure
How to Protect My data from loss?
Of course, the answer to securing your iMac data is to run time-machine backups continuously. By having a current time-machine backup, failed drives can be replaced and data restored without any loss of data.
Many owners of 2017/2018/2019- 21″ iMac's with 1TB HDD's replaced them with third-party SSD's within months of purchase due the very slow and poor performance caused by the extremely slow drives.
iMacs purchased after 2011 are not that easy to upgrade due to having to remove and replace the display to gain access to the drives. One mistake and you can easily crack the display. It is recommend you only have this done by qualified apple technicians.
iMac Fusion drive replacement cost
Add an additional $78 to above prices for the removal of the old fusion drive