Formatted Capacity; Lba Mode; Default Logical Geometry; Physical Organization - Seagate Momentus 7200 RPM Product Manual

3.2

Formatted capacity

Model
ST9750422AS, ST9750421AS,
ST9750420AS and ST9750420ASG
ST9640422AS, ST9640421AS,
ST9640420AS and ST9640420ASG
ST9500424AS, ST9500423AS and
ST9500423ASG
*One Gbyte equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment
and formatting.
3.2.1

LBA mode

When addressing these drives in LBA mode, all blocks (sectors) are consecutively numbered from 0 to n–1,
where n is the number of guaranteed sectors as defined above.
See Section 5.3.1, "Identify Device command" (words 60-61 and 100-103) for additional information about 48-
bit addressing support of drives with capacities over 137GB.
3.3

Default logical geometry

Cylinders Read/write heads
16,383 16
LBA mode
When addressing these drives in LBA mode, all blocks (sectors) are consecutively numbered from 0 to n–1,
where n is the number of guaranteed sectors as defined above.
3.4

Physical organization

Drive model
ST9750422AS, ST9750421AS,
ST9750420AS and ST9750420ASG
ST9640422AS, ST9640421AS,
ST9640420AS and ST9640420ASG
ST9500424AS, ST9500423AS and
ST9500423ASG
Momentus Product Manual, Rev. A
Formatted capacity*
750GB
640GB
500GB
Sectors per track
63
Read/write heads
4
4
3
Guaranteed sectors
1,465,149,168
1,250,284,896
976,773,168
Number of discs
2
2
1
Bytes per sector
512
7