Hard Disk Monitoring

I just bought a box of misc. hard drives last week and one of the drives is a Western Digital Caviar Black 640GB (WD6401AALS).
It passes every test in HD Sentinel and WD's Data Lifeguard as well but...
HD Sentinal says that "problems occured between the communication of the disk and the host 4738 times".

#1 - Is the drive failing ??
#2 - Will this communication problem cause corrupt data ??

I'd like to use this drive in my file server but if it's starting to die I'll RMA it.

Please advise ... thanx.

Thanks for the question.

Usually this problem is not related to the hard disk and I can make sure it does not cause data loss.
(if no other problem is reported, the Health should be 100%).

Such data communication problems are caused by incorrect, loose SATA cable connections.
Hard disks log all of these problems in its lifetime and this is what Hard Disk Sentinel reads and displays.

But in a new system (if proper cables and connections used), these problems can
be completely ignored as they were caused by the old system.

Now (in your system), you may even use Hard Disk Sentinel to reset the error counter:
on SMART page of the drive,
please locate the Ultra ATA CRC error count attribute.
Please locate the "Offset" column for this attribute, click on the 0 between - and +
and enter the number of problems reported but with negative sign ( -4738 ).

This will reset the error-counter to zero. So the error text will be removed from the text description
and it will be displayed again only if there will be new such problems found.

Personally I'd also recommend to use the tests in Hard Disk Sentinel to verify if the drive is
really working correctly, error-free and the stored data is safe.
Please check http://www.hdsentinel.com/faq.php#tests for more information about the
recommended steps.

I hope I could help.

Please let me know if you have any questions.
You may also use Report menu -> Send test report to developer option so I can check the
hard disk status and may advise.

ok, so HD Sentinel is reading a log file and telling me those errors occured on the other persons system.
good to know.
I did the reset and am running another write=read test.
we'll see what happens.

thanx !!

Yes, after reset the test will be perfect method to verify if the situation is stable and fixed.
If things are perfect (no other problems found and in your system both the connections and the cables are perfect), then the text description should not display any errors and the tests should be completed without problems.

Just a note: data transfer errors also could be caused (in this case in system of the previous user) by overclock or general overheat of the system.
If you will ever see any increase of the error-counter again, these may be checked and improved also.

I am wondering what happened to the test you take? Were you able to manage any fix at all?