Most sources say 3-5 years but they are based on assumptions about typical operating hours per year. I could find only one reference to older HDD’s with very few actual operating hours. I am curious because I was thinking about buying an enclosure for my 6 yo WD Caviar Blue salvaged from my old PC. I would say it has only 800-1000 operating hours, tops. Same with my 8-1/2 yo WD Elements portable. I use my Elements to store back-up images. Should I be tossing these older drives and buy new? Or, are they good to go since they have such low operating hours? Thanks.Regardless of whether a drive is brand new or years old, it could fail at any moment.  The best defense against this is redundancy of data.  The more critical your data, the more redundancy.

I don't toss older drives that are still working (that seems a waste to me) but make sure I have good backups of everything so, if a particular drive fails, I can replace it and restore it's contents from my backups. Quote from: strollin on October 31, 2019, 07:23:17 AM

Regardless of whether a drive is brand new or years old, it could fail at any moment.  The best defense against this is redundancy of data.  The more critical your data, the more redundancy.

I don't toss older drives that are still working (that seems a waste to me) but make sure I have good backups of everything so, if a particular drive fails, I can replace it and restore it's contents from my backups.

For Hard Disks, Much like people, age is not necessarily a direct indicator of reliability. things like Mean-Time-Between-Failures don't tell you when you can expect your specific drive to fail; it could fail sooner, or it could last 10 times that amount. It could be completely DOA in the manufacturer packaging, or fail shortly after use, or it could fail after a year or two, or it could last 10 years, etc.

As Strollin said, best approach is to assume a drive can fail at any moment, and, of course, be privvy to the signs of impending failure to take action early- better to have a backup or disk clone and not need it than to have a drive fail that you could have cloned but didn't because you figured it was fine.

For my own anecdote, my PC has a 1TB SSD, a 4TB WD Red and a 4TB WD Blue and I have another 4TB WD Blue as an external. The 1TB SSD as well as the Blue are themselves replacements for a Seagate SSD as well as a 3TB Seagate drive. Once they started to show problems (the SSD was at about 80% of it's percent lifetime used, and the 3TB started to disconnect randomly during intense use. the former still works fine in another non-critical PC, but the 3TB ended up failing outright when used as a similarly non-critical data drive on that same system after removing it.

I've got an identical WD Red and WD Blue as those I have installed waiting in a cupboard (having only been used to verify they weren't DOA) specifically as replacements for the two I have installed.

We published our first “Hard Drive Stats” report just over 5 years ago on January 21, 2014. We titled that report “What Hard Drive Should I Buy.” In hindsight, that might have been a bit of an overreach, but we were publishing data that was basically non-existent otherwise.
Many people like our reports, some don’t, and some really don’t — and that’s fine. From the beginning, the idea was to share our experience and use our data to shine a light on the otherwise opaque world of hard disk drives. We hope you have enjoyed reading our reports and we look forward to publishing them for as long as people find them useful.

Hi artbuc

With putting desktop drives into mains powered en closures there is less problems than laptop drives powered from USB ports.
Main problem with desktop drives is heat and any movement when running.  So a Western Digital Black drive would not be a good drive to put into a external case  without some form of cooling also some cases have tool less plastic mounts which don't have any heat transfer so you would be better with the Green versions of WD drives Seagate do a green drive as well. You don't say the capacity of the WD blue drive you have even some of these run hot.

Most notebook drives draw between 600 ma to about 1 amp from 5v so are not able to operate on a usb 2.0 port or even some usb C ports so reliability is an issue. Drive manufactures of usb drives use designs which draw only 200 ma to 650 ma so start more reliably and are more stable operating. Drives like the Transcend or WD passport power down when not in use.
SSD drives in external cases, most draw over 1 amp current and a cheap SSD can loose a lot of data if the power gets disconnected before it is dismounted.
There is lots of other things to consider this is just some of them.