Hard Disk Monitoring

I'm having a problem with WD GP hard drives. One disk is always perfect, but the second one, brand new, after one week started to show lots of errors on HDSentinel:

"There are 87 bad sectors on the disk surface. The contents of these sectors were moved to the spare area.
Based on the number of remapping operations, the health of the disk was decreased in different steps.
It is recommended to examine the log of the disk regularly. All new problems found will be logged there.
It is recommended to backup immediately to prevent data loss."

The same disk passes the extended test using WD diagnostics, which the tech support told me to run.

Test Option: EXTENDED TEST
Model Number: WDC WD10EACS-00ZJB0
Unit Serial Number: WD-WCASJ1505682
Firmware Number: 01.01B01
Capacity: 1000.20 GB
SMART Status: PASS
Test Result: PASS
Test Time: 13:21:43, May 09, 2009

Test Option: QUICK TEST
Model Number: WDC WD10EACS-00ZJB0
Unit Serial Number: WD-WCASJ1505682
Firmware Number: 01.01B01
Capacity: 1000.20 GB
SMART Status: PASS
Test Result: PASS
Test Time: 13:24:21, May 09, 2009

Now i don't have a clue if the drive is really at risk to be faulty and proceed with the RMA or it's a bug of your software (in the latter case i regret to have paid the registration - i absolutely hate unreliable things, being hardware or software).

I'd like some light on the matter.

Thanks for your question.

You may know that any small, microscopic scratch or dust can cause some bad sectors on the disk surface. Some of them may appear even on a new hard disk after some use.
This problem (alone) is not a big issue, especially, because these sectors are not used any more: the hard disk reallocated them and all read and write operations are redirected to the spare area instead.

That's why the software-based disk surface tests showed no problems at all. This is a very good sign - I'll describe why.

Problem would start only when the number of these sectors slowly but constantly increases (thus further decreasing the health value of the disk). These new and new problems may cause data loss and complete system instability.

Hard Disk Sentinel is sensitive enough to detect all such issues and give textual description based on what it found.
The important thing is that it can detect any slight decrease in the health. For example, you can be notified and can verify any (even very small) problems occured with your hard disk - otherwise such problems may not be noticed, until the disk failure appears.

If you have some time, I recommend to press F1 to open the help and select "Appendix -> Text description" for more information.
The same is available on-line at: http://www.hdsentinel.com/help/en/index.html
In that section, I describe what are the most important in this situation and what are these bad sectors mean.
The most important is that it does not mean that the hard disk should require immediate replacement - especially in terms of warranty.
Warranty replacement is possible only if the drive has enough problems (the exact values are defined by the manufacturer), when the health value is dropped to 0 %. Some drives fail sooner - as it is described at http://www.hdsentinel.com/smart

But as described in the Help, if you can make sure that the status of the drive is stable (the health is constant for a longer period), then you will not need to worry about these issues. You can even "clear" these problems (and restore the health to 100%) - so only further issues and new problems will be logged and will make alerts.

I recommend not only software based read tests - because they may not reveal all problems / issues.
The best is to execute the short and extended hardware self tests of the drive (you can find them in the File menu of Hard Disk Sentinel). If they both complete successfully and you see no further decrease of the health then you can safely reset the number of problems by using a negative offset value at the proper S.M.A.R.T. attribute.

hdsentinel wrote: In that section, I describe what are the most important in this situation and what are these bad sectors mean.
The most important is that it does not mean that the hard disk should require immediate replacement - especially in terms of warranty.
Warranty replacement is possible only if the drive has enough problems (the exact values are defined by the manufacturer), when the health value is dropped to 0 %. Some drives fail sooner - as it is described at http://www.hdsentinel.com/smart

But as described in the Help, if you can make sure that the status of the drive is stable (the health is constant for a longer period), then you will not need to worry about these issues. You can even "clear" these problems (and restore the health to 100%) - so only further issues and new problems will be logged and will make alerts.

I recommend not only software based read tests - because they may not reveal all problems / issues.
The best is to execute the short and extended hardware self tests of the drive (you can find them in the File menu of Hard Disk Sentinel). If they both complete successfully and you see no further decrease of the health then you can safely reset the number of problems by using a negative offset value at the proper S.M.A.R.T. attribute.

Hello,

Thanks for the reply.
I will do the hardware tests, and if all is ok, i'll clear the problems from the program, because seeing a big red X in my notify bar is annoying

The first drive that was sent for RMA had a quick degrading pattern, then i stopped using it, cleared all data and sent away. This was the replacement unit, so they asked some more questions including doing
the WD diagnostics. On top of this, I ran extensive checkdisk (/f /r) and the drive results with 0 bad sectors.

The health status has remained stable.
What i dont understand if the bad sectors are 0 or 87 ???

Thanks for the reply.
I will do the hardware tests, and if all is ok, i'll clear the problems from the program, because seeing a big red X in my notify bar is annoying

The first drive that was sent for RMA had a quick degrading pattern, then i stopped using it, cleared all data and sent away. This was the replacement unit, so they asked some more questions including doing
the WD diagnostics. On top of this, I ran extensive checkdisk (/f /r) and the drive results with 0 bad sectors.

The health status has remained stable.
What i dont understand if the bad sectors are 0 or 87 ???

The important is that the health is stable - so no new bad sectors "born" on the surface.

Chkdsk scans only the file system for errors. Usually it does not find bad sectors because these sectors are not used any more by the drive. Even chkdsk cannot access them - so chkdsk verifies the spare area for those 87 sectors. And because the spare area is perfect, chkdsk reports 0 errors
Usually the bad sectors reported by chkdsk are logical bad sectors only and they "vanish" after a complete re-partition and re-format combination.

Ps. the following versions of Hard Disk Sentinel will have extensive disk testing methods which can be used to examine the disk surface and reveal any problems.