This is actually posted on Microsoft's website to remove Non-Dos partitions, but it will remove all partition tables. I have used it for years to damaged hard drives where the MBR is damaged and cannot be removed to be re-formated any other way.
Code:
Table 1: Debug Script to Erase Hard-Disk Partition Table
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Debug Enter Debug Comments
Prompts Commands
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- A 100 Assemble from CS:0100.
nnnn:0100 INT 13 Call interrupt 13.
nnnn:0102 press the (nnnn in the segment address).
ENTER key
- RAX Replace AX register.
AX 0000
: 0301 Write on sector.
- RBX Replace BX register.
BX 0000
: 0200 Start from ES:200.
- F 200 L 200 0 We want to write zeros.
- RCX Replace CX register.
CX 0000
: 0001 Cylinder, 0, sector 1.
- RDX Replace DX register.
DX 0000
: 0080 First physical hard disk, head
0. (Substitute 0081 for this
entry if you are clearing the
table on the second physical
hard disk, 0082 if you are
clearing the third physical
hard disk, and so forth).
- P Proceed (Debug will display
several lines of information).


