HDD Mystery!

[Kaworu]

Hello all, this may seem like a long dead problem, but I can't seem to find a solution. My WinXPSP2 install won't recognize over 128 gb. I remember the 128gb problem, but I never suffered from it.. The full 320gb used to be avail!  Now, a few months ago I reformatted, and this problem has been around for awhile.  I've just never been able to fix it. Like I said, the SP2 is installed, which should have fixed it. I know the BIOS is fine, as data recovery progs, diag tools, and Data Lifeguard (my hdd is from WD) all recognize the full 320 gb.  :-?

Uggh, no site has yet to be any help. Unfortunately, reformatting agin is not an option either, as this is a family computer, and we can't lose important data.  >:(

[Ivan]

Dont format LBA48 drives with a non-LBA48 capable tool (i think you did this)

[Kaworu]

But if it was a format error, why is the full size still recognized by all other progs? Why is it only Windows that does this?

For Example....

CP/Admin Tools/Computer Management/Disk Management

It's telling me the partition D: is 128gb w/38.25 gb free, however, when we look at the map of the physical disk, it shows the partition taking up all available space...that space being 298gb, exactly what it should be. So, wouldn't this mean that the disk is working and properly configured, but Windows can't "read" it properly?  :-/

This is not my primary boot drive, but a secondary slave drive.

Of course if I'm being a complete idiot, feel free to tell me, but then explain why I'm a complete idiot...because I'm a complete idiot!  ;D

Thanks guys!  :D

[Ivan]

It's telling me the partition D: is 128gb w/38.25 gb free, however, when we look at the map of the physical disk, it shows the partition taking up all available space...that space being 298gb, exactly what it should be. So, wouldn't this mean that the disk is working and properly configured, but Windows can't "read" it properly?

Header is set to 290GB (what the disk manager says in the bar graph), but the last 30GB are actually the first 30GB (the last 30GB marked as 'free space' are not used in the below graph, but are pointing at the wrong position on the disk).

Dunno if you had binary math... but imagine the following
1+1 = 10 if you have space for 2 bits.
If you have only one bit and no overflow checks... 1+1 = 0, which means you start at 0 again, instead of ending up at 2

Now in case of your harddisk the header says 'im 290GB', while the actual size of the partition is 128GB. Now when the head reaches 128GB + 1MB, the first 1MB of the old data is overwritten (as the 128GB + 1MB page is the same as the 1st 1MB page on the disk when you start from 0 bytes).

Better make a backup of the data, remove the partition in disk manager and re-create it. Then you'll get the whole 290GB working correctly.

[Kaworu]

Thanks for the explanation! Course now I've gotta back everything up again. S***!