Data on Disk inaccessible - suddenly unformatted

[jaymax]

Hello,

Win 2K Prof. SP4

Multi Disk System

All NTFS

Reinstalled O/S on one drive - Master on EIDE channel on MOBO

Slave drive on same channel appears normally in POST, but in "My Computer" Listing name appears as "Local Disk (I)" Details of disk size absent. This drive previously had 3 partitions.

Master 58.6 GB; Slave 500 GB, both disk type Basic. Listed as "healthy" on

My Computer>> Manage >> Computer Management >> Disk Management

Slave drive now has no file system listed, and size listed as 128 GB. BIOS setting LBA/Auto for all drives.

Used diskmap:

[DiskSize here incorrect; /d1 = Slave drive]

C:\>diskmap /d1

Cylinders HeadsPerCylinder SectorsPerHead BytesPerSector MediaType

16709 255 63 512 12

TrackSize = 32256, CylinderSize = 8225280, DiskSize = 137436203520 (131069MB)

Signature = 0x00000001

StartingOffset PartitionLength StartingSector PartitionNumber

137438952960 0 1

MBR:

Starting Ending System Relative Total

Cylinder Head Sector Cylinder Head Sector ID Sector Sectors

0 0 52 1023 254 63 0x07 51 771987459

1023 2 28 1023 223 27 0x07 771971598 102396168

1023 223 28 1023 16 63 0x07 874367766 102401370

0 0 0 0 0 0 0x00 0 0

Concerned about Signature = 0x00000001, have always read of it been hex AA55

Now the signature of an identical disk, with only one partition has a signature of

=> Signature = 0x32d28ddc ? now I am a tad bit confused. Could have changed it with a Hex Editor but now I am not sure what it should be changed to.

Used MBRWizard:

C:\>MBRWiz /Disk=1 /List

Disk: 1 Size: 131G CHS: 16709 255 63

Pos MBRndx Type/Name Size Active Hide Start Sector Sectors DL Vol Label

--- ------ ---------- ---- ------ ---- ------------ ------------ -- ----------

0 0 07-NTFS 377G No No 51 771,987,459 I: <None>

1 1 07-NTFS 50G No No 771,971,598 102,396,168 -- <None>

2 2 07-NTFS 50G No No 874,367,766 102,401,370 -- <None>

Oddly enough volume type here is maintained as NTFS but not shown in Disk Management, probably because of disk size.

Attempt at correcting the Labels failed

[Error 106: - Unable to assign label to selected volume]

Restoration of the MBR from a backup copy, showed "... MBR was successfully restored from ..." message but actually remained the same.

Is this a MBR problem, the LBA / 137 Gb barrier or ?

and how do I get around it without destroying the data on the disk?

Thanks!