How long should a hard drive last and are the new solid state drives going to be more reliable?
This question was answered on March 21, 2008. Much of the information contained herein may have changed since posting.
Todays hard drives are faster, store more information and are more reliable than ever before, but just like any other electronic device, it has the possibility of failing
Current hard drives are designed to run non-stop for years and have warranties that range from 1 to 5 years, but that is of little comfort if a 6 month old drive full of your family photos, address books or financial information fails and you dont have a current backup.
A thin attempt at trying to rate the life of a hard drive through MTBF (Mean Time Between Failure) has been around for a long time, but the reason I call it thin is that every manufacturer uses different parameters for publishing this spec.
An MTBF of 700,000 hours equates to about 80 years, which is NOT how long you can expect the hard drive to last, but a rating based on a bunch of math that the manufacturer chose that can be misleading.
MTBF has become in the words of a pundit on the Internet a statistical measure that we are not supposed to believe, so dont take it at face value.
Based on our Data Recovery labs experience over the years, a high MTBF rating is fairly immaterial because the vast majority of the failed drives we are asked to recover data from are less than 3 years old
What makes a hard drive failure unlike any other type of electronic failure is not only do you lose the use of the device, you potentially lose all of the information that is stored on it.
Think about how tragic the failure of your DVD player would be if all your movies and family videos disappeared along with it.
Despite the age and mechanical nature of magnetic hard drives (which were first created in 1956), it continues to be the most economical way to store large amounts of information.
For almost the entire 20 years that I have been involved in the computer industry, I have been hearing the prophecies of the end of the magnetic hard drive.
Despite all of the various alternative storage technologies that have been developed, none have been able to overcome a simple economic equation: the cost per megabyte.
The most recent entry into mass storage is the Solid State Drive (SSD) which is based on the same technology as your digital cameras memory card, just a lot bigger (and a lot more expensive!)
As a point of reference, the current price for a 80GB SSD is over $1500, while a magnetic 80GB drive is less than $60 The SSDs cost per GB will have to come way down before the average Joe has any interest in owning it.
While its true that SSDs have no moving parts, there is no data that suggests that they are more reliable as a result In fact, some are suggesting that since chip failure is more common than drive failure in todays personal computers, it might actually make SSDs less reliable in the long run.
The most interesting thing that I have seen from the mass storage community is what are being labeled hybrid hard drives (HHDs).
Hybrids incorporate the best of todays magnetic technology with a very large Solid State cache drive, which makes the drive faster and consume less battery life making them ideal for laptops.
A cache circuit stores recently accessed information, which reduces the need to go back to the spinning magnetic hard drive which is what speeds up access times.
There are some drawbacks to this method of data storage and access, so the jury is still out as to whether this combination is worth the extra money.
What you really need to take away from this column is this:
There are only two kinds of hard drives; those that have failed and those that are going to fail, so plan accordingly (backup, backup, backup!)
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Posted by Ken Colburn of Data Doctors on March 21, 2008