One of the most important quality specifications, the length of the warranty is one
that can only be considered indirectly technical, because it is more of a
manufacturer policy than a technical measurement. It is however a number that "boils
down" in rough terms the quality of the disk drive, for the simple reason that if a
manufacturer warrants a drive for much longer than the drive actually is expected to last,
they lose a lot of money when the warranty claims come pouring in.
Retail warranties for hard disks are usually either three years or five years in
length. Three-year warranties are typical for consumer-grade (usually IDE/ATA) drives, and five-year warranties are the norm
for "enterprise" class (usually SCSI)
drives. I am not sure if it was by design that these two standards came to be, but they
are fairly universal. It seems likely that the companies match each others' warranty
length to avoid getting into a competitive battle that would stretch warranty lengths out
and cost all of the manufacturers in the end.
Does the fact that a drive has a five-year warranty mean that it is higher in quality
than one with a three-year warranty? The answer is "yes and no". To some extent
these more expensive drives are manufactured to more exacting standards because they are
sold for much higher prices to clients who plan to use them in often-critical business
applications. However, at least some of the motivation behind longer warranties
is to sell the drives as being high quality and/or to match the warranty periods of other
companies. It's a bit of a "chicken-and-egg" situation. And since every drive
you look at it in a given class is likely to have the same length of warranty as any
other, the length of the warranty doesn't do much to help you differentiate between
drives. (Although it does establish a standard for a given class of drive and give you
reason to be suspicious of any drive with a warranty that is much below that standard.)
Here's something else that most people don't really think about--especially those who
recommend high-end drives with five-year warranties over "cheaper" drives with
"only" three-year warranties: are you really still going to be using
that new drive in four years? Considering that most people who buy high-end drives need
high performance, and considering that the performance of today's drives will be a joke
compared to that of drives made in four years, the answer for many people is
"no". The length of the warranty doesn't matter if the drive is sitting in a box
with your leftover stereo cables and that extra printer cable. However, if you tend to buy
a drive and use it for many year, that extra two years of warranty could be quite
valuable.
There's a lot more to a hard disk's warranty than its length; it's quite fair to say
that all warranties are not created equal. For example: what is the manufacturer's policy
for replacing drives that fail during warranty? That's often at least as important as how
long the warranty coverage is. I have written this separate section
to discuss the various issues involved in hard disk warranties.
Next: Hard Disk
Quality and Reliability Issues
