Jtdylktuy

I ran this HD utility called CrystalDiskInfo that displays some of the S.M.A.R.T. information on my drives. It is displaying a "Caution" warning on one of my drives because its "Reallocated Sectors Count" value is 263 (ideally it should be 0 as it is on all of the other drives I have tested).

I posted this question on another forum and the general consensus of the responders was to back up immediately and get rid of the drive. The drive is fairly new and only has 4575 hours on it. I just learned about this utility a few weeks ago, so I don't know when the reallocation of these sectors may have occurred, but it hasn't changed.

Can I trust this drive?

Update (9/27/2009): That reallocated sector count stayed at 293 until about a week ago when I noticed it went up by 1. Just yesterday, I noticed it's up to 659. It's under warranty and is going back to the manufacturer for replacement.

In my experience it's a toss-up. I've had one drive that had some reallocated sectors and a nasty whine that ended up outlasting some drives that gave no warnings before dying a miserable death. I actually chucked it because it was so noisy, rather than data loss.

However, for me, personally, at the first sign of problems in a drive, I backup then swap it off. Drives are cheap, online backups are cheap and if you're anything like me, your time is better spent elsewhere than trying to recover a drive.

I have drive that has 165 of them for a long time now. They all happened at one time and never increased since (two years ago). I would just closely monitor that figure. If it is just one time increase, do not worry.

Rather than just ditching the drive, you might want to just keep an eye on it first, to see if the reallocated sector count increases. If that count continues to increase, the drive is finding and mapping out more and more bad sectors.

I guess it depends on what this drive is doing - is it "mission-critical" or on a server? If so, I would be more nervous than if it's in a home PC not doing a whole lot (as long as you make regular backups of the data, which of course you should do anyways).

Edit: I just downloaded and ran CrystalDiskInfo on my harddrive here at work (an always-on PC, as we're a 24-hour operation), and it's logged 7739 power on hours and has 100 reallocated sectors.

For those who don't know, reallocated sectors are:

Count of reallocated sectors. When the
hard drive finds a
read/write/verification error, it
marks this sector as "reallocated" and
transfers data to a special reserved
area (spare area). This process is
also known as remapping, and
"reallocated" sectors are called
remaps. This is why, on modern hard
disks, "bad blocks" cannot be found
while testing the surface – all bad
blocks are hidden in reallocated
sectors. However, as the number of
reallocated sectors increases, the
read/write speed tends to decrease.
The raw value normally represents a
count of the number of bad sectors
that have been found and remapped.
Thus, the higher the attribute value,
the more sectors the drive has had to
reallocate.

Source: Wikipedia

It depends on how critical the data on the drive is.

You should always keep good backups... but in your case, I would keep an eye on it. If the number of reallocated sectors is not increasing, it might not be a deteriorating problem. It might have been a manufacturing defect or a one-time bump.

If you want to squeeze some more life out of it, I would say "use it." Use it for static data (pictures, music, applications, etc) that you can recover from a backup if the drive fails. But I would tend to prefer my other drives for data that is a bit more important to you.

It might be a sign, but in general you should not be worried
until the reallocation count goes to a high number.

Modern drives are so dense that reallocations are quite
common.

On the Security Now podcast Steve Gibson has talked about
this. See e.g. episode 196, near "there are sectors
that are going bad before they have gone bad. ".