On Sun, 05 Aug 2007 11:38:02 -0700, put finger to
keyboard and composed:

My problem got solved. I ended up downloading GParted (LiveCD). The
Livecd is an iso image that creates a bootable linux cd. GParted is a
partitioning tool. When I booted with the CD, magically, GParted saw
the whole 500Gb.

I suspect my problem was related to what Franc Zabkar had indicated.
Somehow the disk was locked to report a specific size, even though I'd
thought I had zeroed the MBR. Imediately after repartitioning in
GParted, the BIOS then recognized the WD hard drive as a 500Gb drive.
Whew!

Goofy WindowsXP, after an initial reboot, identified the drive as a
one terrabyte drive. But subsequently Identified the drive as it
should've been, 500Gb. Thanks Franc, and the guys at GParted.

Sorry, but I doubt that my input was of any use.

This is what prompted my original suggestion:

http://en.wikipedia.org/wiki/Host_Protected_Area

================================================== ==================
Operating systems use the IDENTIFY DEVICE command to find out the
addressable space of a hard drive. The IDENTIFY DEVICE command queries
a particular register on the IDE controller to establish the size of a
drive.

This register however can be changed using the SET MAX ADDRESS ATA
command. If the value in the register is set to less than the actual
hard drive size then effectively a Host Protected Area is created. It
is protected because the OS will only work with the value in the
register that is returned by the IDENTIFY DEVICE command and thus will
never be able to address the parts of the drive that lie within the
HPA.
================================================== ==================

GParted appears to be confined to the visible areas of the HD. I don't
see any reference in its documentation that would suggest that it is
HPA aware.

- Franc Zabkar
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