SMART status Disk Utility vs Crystal Disk Info (and others)

[imrazor]

Some time ago the 2TB "Fusion drive" in my 2017 5K iMac starting acting weird, so I broke the SSD and HD apart and use them separately now (128GB SSD for Ventura boot, 2TB spinning rust for APFS data + Boot Camp.) When I check the SMART status with Disk Utility in MacOS it simply says "Verified" which sounds like there are no issues. However if I boot up Windows and check the SMART status with Crystal Disk Info (a popular free Windows disk utility) it reports 40 reallocated sectors and shows a caution warning. That said, the drive has shown the same 40 reallocated sectors for a year or year and a half.

Which utility should I believe? Is there cause for concern, and if so, how much concern? I really only use the internal HD for gaming and multimedia playback.

 

[bzgnyc2]

Some time ago the 2TB "Fusion drive" in my 2017 5K iMac starting acting weird, so I broke the SSD and HD apart and use them separately now (128GB SSD for Ventura boot, 2TB spinning rust for APFS data + Boot Camp.) When I check the SMART status with Disk Utility in MacOS it simply says "Verified" which sounds like there are no issues. However if I boot up Windows and check the SMART status with Crystal Disk Info (a popular free Windows disk utility) it reports 40 reallocated sectors and shows a caution warning. That said, the drive has shown the same 40 reallocated sectors for a year or year and a half.

Which utility should I believe? Is there cause for concern, and if so, how much concern? I really only use the internal HD for gaming and multimedia playback.

I would believe the details provided by Crystal Disk Info.

I believe MacOS just reports whether it can see the SMART status the of the drive. It might report if the drive self-reports that it is failing but no one has ever claimed that they got an early warning of a drive failure from MacOS's smart status.

If you want to get a drive's SMART details from the MacOS side, I would use DriveDX (or for the command-line receptive, https://www.smartmontools.org/).

As far as those 40 reallocated sectors, I don't know the exact metric being reported nor the context of it on that drive. I can say generally it is a bad sign if a drive has accumulated so many bad sectors that it has run out of spare sectors to reallocate bad sectors to and is now reducing its capacity below its original capacity to take those bad sectors offline. If it's just 40 reallocated sectors total over the life of the drive relative to factory format and they are coming out of the spare pool, I'd say it's fine.

As far as preemptive replacement, it depends on how much a drive failure would cost you. If the cost of the lost data and/or lost time (even assuming a backup, there's typically lost time) is more than $300 or $400, I would replace the drive preemptively on my schedule. In the case of an old iMac that you may not want to take apart, perhaps switch the data to a new external. On the other hand if the worst case is you can't play games on that computer for a week or two at some future indeterminate time in the future, I would probably let it ride and see what happens.