hard drive seems ok, but the file content changes when copying bigfiles

[Bill]

I bought an Acer X1200 computer about 10 month ago and it didn't work
well from day one. Sometimes I found the machine needs to check the
file system when I boot it - and the worst is, when I copy big files,
the file content changes by itself! The first thing I suspect was
virus. But it is NOT. I did a fresh installation using XP, VISTA, same
issue. I even used the Redhat Fedora live CD (running the OS from CD
disc) to copy the files, I still get the same result - the copid file
is different with the original one (file size is same). I used this
hard drive on other machines, same issue. That means the problem is
not operating system, not virus, not mother board or Memory, but the
hard disk itself.

The hard disk seems operating fine. No bad sector, no fanky noise, no
nothing, and windows never complains the hard drive (except sometimes
I cannot unzip file - or the newly copied exe file cannot excute -
that is because the file content was changed during copy). I am able
to do a low-level format on the drive and now error.

The hard drive is WD3200AAJS. (Western Digital).
I downloaded the data lifeguard for windows from Wesetern Digital
website and run the diagnostic from windows. The QUICK test and the
extend test ran successfully. My question - does the DLG has a
function to do write and read back verification? I strongly suspect
the writing function has issue.

After I noticed this issue, now each time I use copy /v (/v mean
verification), to copy files, for small ASCII files, no issue. But the
big avi or zip files, more half verification fails.

I am trying to find a good hard disk diagnostic tool, but not sure
whethere is any available over there. I need some tools that I can
boot the machine and detect the hard drive. The WD DLG 5.04 for DOS
will not see the hard disk as the DOS version doesn't have the SATA
driver for the SATA controller in the NVidia chipset GeForce 8200.

Thanks.

 

[Grinder]

I bought an Acer X1200 computer about 10 month ago and it didn't work
well from day one. Sometimes I found the machine needs to check the
file system when I boot it - and the worst is, when I copy big files,
the file content changes by itself! The first thing I suspect was
virus. But it is NOT. I did a fresh installation using XP, VISTA, same
issue. I even used the Redhat Fedora live CD (running the OS from CD
disc) to copy the files, I still get the same result - the copid file
is different with the original one (file size is same). I used this
hard drive on other machines, same issue. That means the problem is
not operating system, not virus, not mother board or Memory, but the
hard disk itself.

The hard disk seems operating fine. No bad sector, no fanky noise, no
nothing, and windows never complains the hard drive (except sometimes
I cannot unzip file - or the newly copied exe file cannot excute -
that is because the file content was changed during copy). I am able
to do a low-level format on the drive and now error.

The hard drive is WD3200AAJS. (Western Digital).
I downloaded the data lifeguard for windows from Wesetern Digital
website and run the diagnostic from windows. The QUICK test and the
extend test ran successfully. My question - does the DLG has a
function to do write and read back verification? I strongly suspect
the writing function has issue.

After I noticed this issue, now each time I use copy /v (/v mean
verification), to copy files, for small ASCII files, no issue. But the
big avi or zip files, more half verification fails.

I am trying to find a good hard disk diagnostic tool, but not sure
whethere is any available over there. I need some tools that I can
boot the machine and detect the hard drive. The WD DLG 5.04 for DOS
will not see the hard disk as the DOS version doesn't have the SATA
driver for the SATA controller in the NVidia chipset GeForce 8200.

You appear to have a good argument for a warranty claim. Have you
checked with your manufacturer?

 

[David W. Hodgins]

issue. I even used the Redhat Fedora live CD (running the OS from CD
disc) to copy the files, I still get the same result - the copid file
is different with the original one (file size is same). I used this
I am trying to find a good hard disk diagnostic tool, but not sure

In linux, open a terminal, and run "sudo fdisk -l", to find out what
the device name is for the partition used on that drive. It will
probably be either /dev/sda1, or /dev/hda1.

First run "sudo smartctl -a /dev/sda" (Note, no partition number, just
a drive identifier, which may be /dev/hda instead). This will show
if the drive supports smart, and if it has detected any errors.

Then run "sudo badblocks -n /dev/sda1" (Or /dev/hda1, if appropriate).
This will run a non-destructive read/write test on each block, to
see if the data appears to change. If you don't care about the data
on that partition, try "sudo badblocks -w /dev/sda1" instead. This
will try writing various patters, to see if any, and which patterns
fail.

I haven't tried the fedora live cd, but would be surprised if it
doesn't include the badblocks or smartctl commands.

Regards, Dave Hodgins

 

[David W. Hodgins]

This is a fairly rare thing to have happen to a drive,
usually it is the computer corrupting the data instead of
the drive.

I'm wondering if a bad cable, or connector, would result in
this type of behaviour.

Regards, Dave Hodgins

 

[Paul]

I'm wondering if a bad cable, or connector, would result in
this type of behaviour.

Regards, Dave Hodgins

The cable is protected by CRC.

http://www.interfacebus.com/HDD_SATA_Bus.html

The thing is though, I don't know if there is any way
to monitor for those errors. If you get CRC read errors,
those are likely coming from the platter. I don't know if
there is any way you can see cable errors, and know just
how bad your cable is. So if the cable is heavily
errored, eventually an errored packet will get through.
The CRC can't catch everything.

Paul