Hard Disk Monitoring

Any advice for buying a used hard drive?
How to avoid any tricks that sellers use to hide known problems?

Are refurbished drives safe or likely to have recurring problems?

Locally, here in Indonesia, there are many 100% health drives for sale that are 9+ years old with zero or under 100 hours.

I have avoided "100% heath with 0 hours" because I fear that someone may have simply reset it and then as soon as I use it, it will start logging errors.

I just bought one 4 year old drive with:

• Performance: 100%
  Health: 100%
  Power on time: 75 days
  Est. remaining life: 1000 days
  Total start/stop count: 982

Because I figured that if 100% health after 75 days, then, even if it was reset earlier, it's doing ok.
Is that sound logic?

After receiving it:
4tb WDC WD40EMRX-82UZ0N0
Disk > Device Specific Information says:

• Last error (hour) : Never
  Error free hours : 1822 (75 days, 22 hours)

That's after I did Surface Test > Disk Reinitialization, which had no errors. So I feel comfortable with that.

But I'm looking for an additional drive and wondering what the best approach is.

Any drive can fail at any time but how to avoid any tricks that sellers use to hide known problems?

Thanks in advance.
================
(As an aside, here in Indonesia, on the platform Tokopedia, I saw a drive that looked interesting but then saw that same photo at 4 different stores. Who actually has that drive and who is drop-shipping it? Do any of them actually have that 1 year old drive or are they going to send me a 9 year old one? I have asked for a photo of the label, bottom and HD Sentinel screenshot of the drive in their possession. Even though they all said "available, just like the photo, please order.", none have send photos yet. Plus, they say "it's at my offline store, I will photograph later." but I can't find any offline store by that name. All are small stores with little history. Sometimes one person runs stores under multiple names but these seem like 4 different people since responding in different styles at different times.

My old backup drives are failing. IDE ones mostly failed. Some sata from 2008 failed, as well as one that's only 4 years old. So, I need to deduplicate and get things onto newer drives. I only had consumer drives. Thought a NAS drive might be more reliable but then read that they don't spend as much time retrying bad sectors (because intended for RAID that doesn't want to wait and doesn't need to because of redundant data), so if one does start to fail then I'm more likely to lose things. So, now I'm thinking that an Enterprise drive, like Ultrastar, has better reliability while also being suitable for use as a single drive.

Those four stores show the photos of a Jan 2022 8TB Ultrastar with 100% health, 97 days & 2300 start/stop, at 40 to 50% of the price new, which seems reasonable to me, but what do I know? (Some people are trying to sell drives from 2014 at 50% of the new price, which seems crazy to me. I assume that they hope for buyers that don't read the lable or understand the date code.)

I can completely understand and agree your practices:

> I have avoided "100% heath with 0 hours"
..
> I figured that if 100% health after 75 days, then, even if it was reset earlier, it's doing ok. Is that sound logic?

Yes, this is perfect logic. Personally I'd do the same: I'd trust a drive MORE which used for many days (and remains error-free).


Generally when you buy used / 2nd hand drives I'd recommend to (in addition to quickly check the displayed Health % value and Power on time on the Overview page)

1) Check other attributes on the S.M.A.R.T. page which may reflect actual use.
If a hard disk drive has very low power on time (eg. only some hours) then it should not have thousands (or more) at attribute
4 Start/Stop Count
12 Drive Power Cycle count and/or
193 Load/unload cycle count (if these available, as it depends on the model)

2) Check the Disk menu -> Device Specific Information page as it reads additional details from the drive (if available).
It shows (in addition to other details) the internal error logs and the log of self tests started - and when these tests happened (in the lifetime of the drive).
For example, if it shows that a short self test / extended self test executed at the age of 300 days of a "new" drive, it is suspicious...

And regardless of the values and attributes (really) I always recommend to perform INTENSIVE testing as suggested at Support -> Frequently Asked Questions -> Hard disk health is low or recently changed or I just installed a new (used) hard disk. How can I perform a deep analysis?
https://www.hdsentinel.com/faq.php#tests

To summarize, the following steps are the best to detect and repair hard disk problems:
1) Disk -> Short self test
2) Disk -> Extended self test
3) Disk -> Surface test -> Read test
4) Disk -> Surface test -> Reinitialize disk surface

The combination of these disk tests designed exactly to verify the status, reveal any (even minor) issue - or confirm that the drive is generally error-free.
If these report error - then it is better to replace (ideally the seller should offer at least some days warranty for a 2nd hand drive).