Storage forum

General discussion

Is there a life expectancy on external hard drives?

by Lee Koo (ADMIN) CNET staff/forum admin / May 22, 2009 5:57 AM PDT

Is there a life expectancy on external hard drives?

I have been using the same 250GB external hard drive for more than five years. I backup quicken files, thousands of photos and a lot of other files to a portable drive several times a year. I would like to know if it has a life expectancy and should I eventually retire it? Are there maintenance procedures that will enable me to prolong the life of these drives or is it just a matter of luck when it goes south? Thanks so much!

Submitted by: Ted V.

Here are some featured member answers to get you started, but
please read all the advice and suggestions that our
members have contributed to this question.

Life expectancy of external hard drives varies --Submitted by ben_myers

Life span? Definitely! --Submitted by Zorched

Life expectancy --Submitted by Hforman

Do external hard drives have a life expectancy? --Submitted by StephanBer

Life of an external hard drive --Submitted by waytron

Is there a life expectancy on external hard drives? --Submitted by alswilling

If you have additional information and advice for Ted, please click on the reply link and post your answer. Please provide as much detail and information as possible in your answer. If you have proven facts, laboratory researches done, or referenced materials done for this topic please cite those resource and links in your answers to give credit to those folks who deserve it. Thank you!
Discussion is locked
You are posting a reply to: Is there a life expectancy on external hard drives?
The posting of advertisements, profanity, or personal attacks is prohibited. Please refer to our CNET Forums policies for details. All submitted content is subject to our Terms of Use.
Track this discussion and email me when there are updates

If you're asking for technical help, please be sure to include all your system info, including operating system, model number, and any other specifics related to the problem. Also please exercise your best judgment when posting in the forums--revealing personal information such as your e-mail address, telephone number, and address is not recommended.

You are reporting the following post: Is there a life expectancy on external hard drives?
This post has been flagged and will be reviewed by our staff. Thank you for helping us maintain CNET's great community.
Sorry, there was a problem flagging this post. Please try again now or at a later time.
If you believe this post is offensive or violates the CNET Forums' Usage policies, you can report it below (this will not automatically remove the post). Once reported, our moderators will be notified and the post will be reviewed.
Collapse -
Is there a life expectancy on external hard drives?
by dahump / May 22, 2009 10:22 AM PDT

I don't know about 5 years. My WD died after 2 years.

Collapse -
Look after them, and they should last longer.
by TreknologyNet / May 29, 2009 10:08 PM PDT

Unless you're tossing an external drive around like a USB key, and allowing it bounce around in the trunk of the car, I fail to see why an "external" drive should fail any sooner than an "internal" one--they are the same devices, just in different cases--as others have cited, some external enclosures are abyssmal when it comes to ventilation, and that's how I lost a 420GiB backup drive.

Of course Murphy was looking over my shoulder at the time, and made sure that the actual failure occurred while three 160GiB drives were in a state of flux.

Collapse -
Life Expectancy
by mafmusic / May 22, 2009 10:35 AM PDT

Of course it has a life expectancy (like everything else in the universe) but I don't think it is possible to predict when it will fail.

I have a MAC PRO with 4 internal drives and 2 external drives. I have had two of the internal drives for many years.

I routinely use Tech Tool Pro to examine the drive volumes and files. Just to make sure all looks OK. there are many other such tools for MAC and PC. Some come with the computer and are free (like the Disk utility for the MAC).

I believe that routine maintenance should help to extend the life of the drive.

To be sure, I am a computer hobbyist, so I am sure pros will be able to provide more detail.

But BACK UP, and then BACK UP, and then BACK UP some more.
I use Time Machine in MAC OSX to routinely back up all drives.
Plus, I place critical files on the Apple iDisk, just in case the main drives and the backup drive fail.

Monterey CA

Collapse -
Not honey.....
by ackmondual / May 29, 2009 1:20 PM PDT
In reply to: Life Expectancy

I hear honey is the only food in the world that doesn't expire. Ever.

Collapse -
by crazydragon55 / June 4, 2009 3:17 AM PDT
In reply to: Not honey.....

About Honey,It will dry up and turn to sugar in time,Now Twinkie on the other hand will last for years and years,They say they can last for more than 50 years if keep in a cool dry place,Now thats some life expectancy.The food will almost out live you lol.The food that will be around long after there is no other food options left.I could go on about the food shortage problems in the future,But I think we are all aware of the enviable,There will be no food due to globle warming,Famine,Drought and so on.The future is bleak,So enjoy what you have now.

~Crazy Dragon~

Collapse -
It Depends Upon how Much You Use it
by Headspin / May 22, 2009 10:39 AM PDT

Typically, your interior hard drives can have an expectancy to last around 3 years average. As far as exterior hard drives go, you can probably double that range since, for the most part, they are not running with your computer every time it is booted up. Now, depending upon how you keep it stored (usually in a cool, dry area), and the amount of time you use it will add to, or subtract from the time life of your exterior hard drive. Also, if you are able to, open up the device about every six months and take a can of pressurized air and blow out any excess dust that may be lingering. I hope this helps!


Collapse -
Yes, there is
by btberlin / May 22, 2009 10:43 AM PDT

There is definitely a life expectancy to hard drives, just as there is with any electronic device. The expectancy is related to the MTBF or mean time before failure - however, the mtbf is a mean - that is, it represents the average failure rate for the entire population of drives. This value is generally very high, but it only tells you something about the likelihood that your drive will fail. There is no way to tell exactly how long the drive will last. However, there is another interesting relationship between the age of the drive (or any electronics) and the likelihood of failure. The relationship when graphed forms what is called a bathtub curve - it tells us that there is a relatively high failure rate initially and after some (usually long) period of time, and that once the drive has survived the initial likelihood of failure, it is likely to remain functioning for a long period of time and then fail at its end of life. Again - these two concepts predict behavior of the entire population of drives - i.e., all of the similar drives ever manufactured and upon which the failure rates are based. That said, there isn't much you can do to guess when YOUR drive will fail (which it inevitably will). So - how to encourage longevity? Run it for a few weeks without keeping critical data on it - some people refer to this period as burning in. Then, keep it as cool as possible - perhaps with a fan or by making sure it is never on top of other powered equipment. If there are air vents in the case, make sure they are never blocked, which generally means, don't put the drive down on a carpet or some other surface with a nap or that will allow the drive to sink into the surface, like a pillow. That's about all you can do. For totally critical data, most IT departments will back up data onto tape (or sometimes DVD nowadays), and keep the recorded medium geographically separated from the drive or in a firesafe. Personally, in my Linux workstation, i keep two drives for data, and mirror them every night. If you can afford two external drives, you might want to do the same - copy your data to each drive from the internal drive. Good luck.

Collapse -
Life expectancy terminates when you need the data!
by aeparker / May 22, 2009 10:52 AM PDT

Murphy's Law says that your external backup drive will cease to function the first time you really need it, no matter how long you have owned it or how many times you have used it. Having been involved with computers since 1971, I've seen most of the worst case horror stories up close & personal, including "our data center burned up last night with all of our backups in it"... (not my doings!)

I suggest you purchase at least one additional backup device - the cost is SO much less than five years ago! My personal preference is for three devices - grandfather, father & son, and you should keep at least two of these at a different location than your computer, like at work or in a safety deposit box. I saw a 500GB external drive today for $59, so the cost is minimal to actually have 3 separate backups.

Collapse -
External Hardrive Reliability
by galvang / May 22, 2009 10:56 AM PDT

It's tough to determine External HD reliability unless the manufacture has completed real life reliability tests. Some manufactures have the capability of completing these tests however it is expensive. With budget cuts and companies revenues on the line you can bet that these tests have been eliminated.

There is another method however it is not accurate. The manufacturer can complete a reliability prediction called MTBF predictions. MTBF (Mean Time between Failures). It is calculated by several methods. This method is often used in place of life tests. It is expressed in hours.

I would suggest for you to contact the manufacturer of the external drive and ask for the specification for reliability. Ask whether it is from real life tests or is it calculated by using the above method- MTBF predictions. Good luck. It figures WD had a failure.

Collapse -
Re: Is there a life expectancy on external drives?
by kmanley57 / May 22, 2009 10:56 AM PDT

Yes they do and it is usually in 1000's to 10,000's of hours, of operation. However that is just a guideline, and your drive can die before then. So there is no set and rigid time of life for a drive. You just have to hope your drive will last to the expected time is used up. There are smartdrive utilities that can query the function that is built-in to most drives software nowdays and it will give you a report(abet cryptic) that shows how much time you drive has been on, and if it has had any errors during its life that you can check. Which will give you a warning before you start having problem with it 'usually'.

Collapse -
Would like more info on the kmanley5 post
by Ancient-One / May 30, 2009 4:02 AM PDT

Though computing for many years, still classify myself as a hobbist.
Would like to know more about the Smart Drive utilities mentioned by kmanley57 - that checks use time, problems, etc. on externals. Running XP/Pro on Dell Inspiron 530 - Using Acronis 11.0 backup program.
I run 2 identical external HD backups. One is fan cooled, and both are on -- one at a time, on demand only, then shut off. Both are about a year old. Though I think I'm well covered, I still have doubts.

Collapse -
by 1quazzarr / May 22, 2009 10:59 AM PDT

I have had 2 of external hard drives die after only 1 1/2 to 2 years...

I have been told not to move them when they are running.


Collapse -
by donwoodruff / May 31, 2009 1:05 PM PDT
In reply to: HARD DRIVE LIFE


That's only common sense!

Collapse -
Life Expectancy
by drronlech / May 22, 2009 11:04 AM PDT

I consider the warranty period to be the life expectancy. External hard drives have a much shorter warranty than internal hard drives. Therefore the best "external" hard drive would be to use an external docking station that allows for internal hard drives such as Thermaltake's BlacX unit. USB 2.0 and/or eSATA connectivity. Another way would be to place an internal hard drive into an external hard drive enclosure. With the price of hard drives going down as fast as they are, the simplest and easiest method is to use the external docking station. Due to it being a bare internal hard drive you would need to protect it while stored. If you kill the drive, just RMA it. Works for me.

Collapse -
Seagate 7200.11
by drronlech / May 30, 2009 9:32 PM PDT
In reply to: Life Expectancy

As soon as I learned of the firmware problem on the 7200.11 drives, the life expectancy of those drives became ZERO. All servers were in RAID 1 format, so I gradually replaced one channel and eventually the other with Western Digital Black Drives with 5 yr warranties.

Collapse -
by kevsmail / May 22, 2009 11:07 AM PDT

It is a mechanical device, and mechanical devices wear out by their very nature - bearings wear out, motors die.

I look at external drives as almost disposable nowadays. I had a WD 300GB MyBook croak after 1 year + 2 weeks, just out of warranty. Now, I use a combination of DVDs and an external 500GB Maxtor drive. I'll probably move the data from the Maxtor to a new external drive in 2 years or so, before it dies with all my data.

Collapse -
Hard drive expectancy?
by kostas 6 / May 31, 2009 4:08 PM PDT
In reply to: Definitely!

Ihave the same question.Iam always use LACIE hard drive for over 4 years ago.The quarantee ended before3 years,Iam usually stored data,photo,music movies and backup data.What did you suggested?

Collapse -
LIfe expectancy of a hard drive
by m047375 / May 22, 2009 11:38 AM PDT

There can be no realistic life "expactancy" projection for hard disk mechanisms. MTBF you can look up and it speaks for itself. I do not see how anyone can provide a reasonable outlook to the question. Well, other than manufacturing 'knowing' they have put in potentially weak parts because corporate decided to save $$ or knowledge of a flaw etc. However, this won't be public.

You have made it 5 yrs so you are doing the right thing whatever that is. Saying that the moving parts don't fail and you continue to keep it in good care ( users can crash externals in one slight movement); Let's say it continues to work. Then it is extimated that the platters can take reads and write overs to over 100,000 times. In perspective that is over 270 years if you did a backup every day!

'magnetic spacing loss theory' is used to characterize the head-media separation as a function of temperature, altitude, humidity, and HDD operating mode.
However there is no definitive research as models are still being defined to test these factors.

Collapse -
Yes there is
by little peasant / May 30, 2009 10:54 AM PDT

Hello i'm a student MCT at HoWest Belgium.

and according to what we've seen in class, i can only conclude that there is a life expectancy for both USB hard drives, flash drives, SSD, ...

this is due to the fact that most datastorage devices are based on the same theory, to isolate electrons. They use different isolators in each hard drive and the life expectancy of the hard drive can be "calculated" knowing the isolators used in the hard drive.

Though most of the time the malfunctioning of a storage device isn't due to the isolator material, but due to some other factor, ...

There is one advice i can give you.

Which is to never try to save money on storage devices, seriously don't.

Cause i've heard people say "OOH look a 500 GB hard drive for only 50 euro !", but when you read online forums about those hard drives, you're more likely to find hundreds of topics listing failures and malfunctions, etc ...

i myself have been using packard bell hard drives for quite some time now and they're very easy to use and hardly ever malfunction.

If you are keen on having a good hard drive, i'd advice you to spend a couple 100 extra and buy a solid state disk. They're the best of the best out there and are a LOT faster.

Collapse -
But what about L-E with STORED drives???
by splungekid / May 31, 2009 1:03 PM PDT

Several photographer friends use external drives to store their photography. Once a drive is filled, it is placed upon a shelf for future retrieval. Unused except for that moment of need. They are convinced that this procedure is safer than using CD / DVD media as backup.
I am not educated in this field, however, it would seem reasonable that an item designed to spin, would actually fail in a much shorter run time after sitting idle for lengths of time. This therefore would actually mean that your external drive security would basically extend to the current drive being used.
Perhaps this is too far off topic. In real life I know 2 people whose total of 3 external drives have failed by simply sitting on the shelf, and definitely not due to hours run.
Any thoughts?

Collapse -
External Hard Drive life expectancy
by letmepicyou / May 22, 2009 11:43 AM PDT

According to A+ course work (and personal experience), the magnetic bit strength of any hard drive has a half-life of around 5 years. That means the strength of the magnetic particles on the surface of a hard drive have lost 50% of their field strength in 5 years time. Not to mention the fact most external hard drives get much less cooling than the hard drive in a typical computer. If you ask me, I would say it's time to get a new external hard drive, keep using the old one till it dies, but begin making back-ups of your back-ups using another external now, in case the old one does fail. Most hard drives I've seen that don't fail in the first year, fail after about 5 years.
Good luck and remember, keep backing up!

Collapse -
hard drive heading for the grave yard
by tom56071 / May 22, 2009 12:01 PM PDT

they go to the perly gates like everything with out warning id back up your stuff as much as possible heard drives only last so many hours it depends how much you use it once they go your stuff can be lost you then have to go to someone that can hack the stuff off the plate in the drive

Collapse -
Hard Drive Life Expectancy
by Fi0S-Dave / May 22, 2009 12:14 PM PDT

Methinks you are overdue for a drive replacement!
Drives DO wear out. Newer drives have S.M.A.R.T technology that monitors the drive's condition and can report problems. Routines can check the surface and block bad sectors, moving the data to a good sector, however, this not only reduces the drives capacity, but causes fragmentation problems. With the cost of today's drives plummeting, your best bet is to spring for a new (probably faster, quieter and cooler) drive and save the old one as a backup, or for test purposes. I've seen current 1 TB (yes, that's Terabyte!) drives for $75 or less. Smaller drives for MUCH less!

Good luck - but don't count on luck!


Collapse -
Hard drive space
by yenaro / May 29, 2009 6:13 PM PDT

I had a hard disk of 80 GB, now after seven years, I can hardly use only 20 GB of it. Space is important.

Collapse -
Sometimes it's the interface that fails, not the drive.
by Reinstall / May 30, 2009 6:11 AM PDT
In reply to: Hard drive space

I've had several external drives fail, once it was a blown diode in the power section, another it was an IC on the driver board. Both times I was able to pull the actual drive and install in another case, which was very inexpensive.

Remember to never unplug a powered up drive by pulling the end of the power adapter that connects to the drive, pull the 120vac side first.

There's a voltage spike when the field collapses in a inductor, etc, that can create a spike that can fail something down stream,(talking external drives that are powered with a 120vac adapter).

Collapse -
Why are you worried?
by shanedr / May 29, 2009 10:20 PM PDT

The odds of an external hard drive failing when the hard drive you need to reinstall your backed up data to has failed is so remote that it shouldn't be a concern.

Run your external hard drive until it fails or shows signs of failure. Then replace it and do an immediate back-up.

Best of all situations is when you have a desktop and a laptop that you use. I update each computer from the other by flash drive. Then at back-up time I back-up one, then restore from back-up the other. Which leaves me with three identical drives. If one of your computers has a second hard drive then before I do a back-up I use the old back-up to place an older back-up on that extra hard drive. Then overwrite the external hard drive with the new back-up. That way I have three copies of my data plus an older version on that extra internal drive just in case something has recently corrupted my data. The time between back-ups should be enough time to discover if my data has become corrupted.

One thing I do for further protection is to keep my external hard drive in a fire safe.

For the paranoid a second external hard drive with alternating with one kept in a safe deposit box at your bank should satisfy the most paranoid.

But even with that I cannot see any value in replacing a hard drive before it has failed or shows signs of failure.

Collapse -
Life expectancy of external hard drives varies
by ben_myers / May 22, 2009 12:15 PM PDT

The life expectancy of external hard drives varies. Let's rephrase the question: "What can I do to get the longest life out of an external hard drive?"

To look at the problem from the point of view of a hardware engineer, you want minimize wear on the bearings of the spinning drive platters inside and you want to make sure that the drive does not get jolted, especially when it is powered up. A third, and possibly minor consideration is heat. The external drive casing needs to be well ventilated to keep the drive from overheating.

If you are using an external hard drive as additional storage for your desktop or laptop, make sure you power down the external drive whenever you power down the system.

If you are using an external drive only for backing up data, you want to have it powered up when in use, powered down when done, and kept in a safe place when not in use.

Always handle the drive carefully, so it won't get dropped or subjected to many Gs of force.

I have clients who have used external drives for backup for about 5 years now, and the drives still work perfectly. How long an external drive lasts depends on how well you care for it.

Personally, there are some brands of drives I avoid, due to unfavorable past experiences. And every brand of drive has its models which are absolute dogs. The drive manufacturers compete very aggressively on price, price, price, with seldom a mention of reliability predictions. I suppose I could annoy one or more drive manufacturers by saying what those brands are, but I won't.

... Ben Myers

Collapse -
Life Span? Definitely!
by Zorched / May 22, 2009 1:52 PM PDT

Understand first that a company will only warranty a device for a period of time that is statistically beneficial for them. In other words, if they find that a large number of their drives start failing after three years, they most likely won't warranty them beyond that three years. My new fridge (supposedly a 20 year appliance) came with a 1-year warranty. Gives you faith in the quality of manufactured goods these days, doesn't it?

Where I'm going with this is the fact that the two biggest manufacturers have their warranty periods at 3 years. Beyond that the failure curves go up to the point where it's not financially feasible to warranty them. Most drives become iffy after 5 years, but as said before by others there are mitigating factors involved.

Humidity and temperature. If either is too high for prolonged periods, the lifespan will decrease. If the humidity is too low, you have to be more careful about static shocks, but not lifespan.

Type of enclosure. A plastic enclosure insulates the drive and does not allow for heat to be transferred away to the exterior of the enclosure. The only way around this is to either adequately perforate the enclosure or add a fan. If either of these cases are present, then you are okay. A metal enclosure effectively becomes a heatsink for the drive and promotes dissipation as long as the drive touches the enclosure walls.

Amount of time run. If you don't power the drive with each boot of the computer, then its effective lifespan will be longer. If you run it 24/7 then it won't last as long. It's kind of like a car in that regard. In the same vein, if you don't run it at all for long periods of time and the humidity is high, the bearings could rust. Also, if there is a lot of heavy data usage, then it may wear out sooner. Just sitting there spinning is not so bad for it, but if it's clicking and buzzing all the time, then the head arms are what's making that noise and they could wear out sooner. Defragging a drive can help with this type of wear.

All of this boiled down: yes, they do have a lifespan. Yes, you should replace it soon if you want to have a reliable backup. I replace mine every three years as the warranties expire. They're cheap enough now that it's not too big of a deal. I honestly have two forms of backup: Periodic DVD backups and a regular hard drive one.

I keep the old ones around for a while, just in case I need a backup. DO NOT just give the old drive away without making sure you erase and repartition the drive. If you want to be absolutely sure, then use a data shredder app, erase everything, repartition it, and do a long format. If disposing of a hard drive, I take the circuit board off the back and recycle it properly, then beat the drive with a sledge hammer. It's great stress relief. The reason for this paranoia is that if someone gets a hold of the drive and reconstructs the data, then I might as well just hand them my quicken files in person and say, "here, take it for free!"

Collapse -
by EscapePod / May 30, 2009 12:41 AM PDT
In reply to: Life Span? Definitely!

Refrigerators, and stoves, etc., come with 1-year warranties so that the manufacturers and retailers can SELL you extended warranties -- no other reason.

Collapse -
Looking for a smarter drive helps...
by bob.taylor / June 1, 2009 12:18 AM PDT
In reply to: Life Span? Definitely!

All mechanical things will eventually wear - as in "normal wear and tear". I like to think of it in terms of revolutions - whether it's a washing machine, power drill, or hard drive - the little bits and pieces only have so many revolutions of life before they eventually give out.

Getting a drive that knows when to stop spinning, or managing that cycle yourself by only connecting and powering up when you're performing a backup, will maximize the life of the machine.

The counter argument is based on constant environment - powering up and down causes thermal variations - heat and cool - expand and contract - another factor in the life-cycle calculation.

Popular Forums
Computer Newbies 10,686 discussions
Computer Help 54,365 discussions
Laptops 21,181 discussions
Networking & Wireless 16,313 discussions
Phones 17,137 discussions
Security 31,287 discussions
TVs & Home Theaters 22,101 discussions
Windows 7 8,164 discussions
Windows 10 2,657 discussions

Does BMW or Volvo do it best?

Pint-size luxury and funky style

Shopping for a new car this weekend? See how the BMW X2 stacks up against the Volvo XC40 in our side-by-side comparison.