JIM HOLSONBACK wrote in a message to ALL:

 JH> Hello, ALL.

 JH> I was recently trying to use the WD Data Lifeguard diagnostics
 JH> diskette to try and wake up a HDD which FDISK could not detect.

 JH> Here's the strange part - - per its label, the Drive is a WD Caviar
 JH> 5.1 GB,  Model AC35100,  CHS of 10672/15/63 (LBA Translation
 JH> 667/240/63?). But my mainboard autodetects it as 11184/15/63, and
 JH> recommends an LBA translation of 699/240/63. When I run the WD
 JH> diagnostics, it detects the HDD as 5.4 GB, WD Model AC35400L.  The
 JH> WD utility "write zeroes" seems to work on it, but takes a loooong
 JH> time - a couple hours to get thru the first couple percent of the
 JH> drive.  FDISK still wouldn't work after that.

 JH> My only SWAG so far is that the Make, model, chs etc. of the drive
 JH> are stored on a PROM or EPROM chip on the circuit board, and that
 JH> someone swapped circuit boards on this drive, in hopes of making a
 JH> Frankenstein and bringing it to life.

 JH> Any other guesses/insights/advice will be appreciated.

Seems more likely to me that they used an eeprom,  and that something
stomped on it...

And if you want to "write zeros" you can do only the first
portion of it with dd,  under linux,  and not have to do the whole thing
which is apparently what that utility you mention is doing that's so
time-consuming.

*Way* back when,  I actually tried to swap boards to get a HD going,  that
was a couple of different revisions of ST251,  40M MFM drives,  and since
one had a red LED and the other a green one,  it didn't work,  the
revisions of the board were too different.  No way I'd even think about
trying that these days.

Particularly since the bad sector and bad track mapping is probably put
into that eeprom at the factory.

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