Seagate ST12550N/ND/W/WD, ST11950N/ND/W/WD manual Characteristics ST12550N/ND ST12550W/WD

ST11950 and ST12550 Installation Guide, Rev. D 15

Characteristics	ST12550N/ND		ST12550W/WD
Interface	Fast SCSI-21		Fast & Wide SCSI-21
Multi-seg. cache	1,024	Kbytes	1,024	Kbytes (W)
			512 Kbytes (WD)
Capacity
Unformatted	2,572	Mbytes	2,572	Mbytes
Formatted2	2,139	Mbytes	2,139	Mbytes
Recording
Cylinders (user)	2,707		2,707
Heads	19		19
Avg sectors/track	81 (51h)		81 (51h)
Avg bytes/track	49,768		49,768
Modulation	RLL 1,7 code		RLL 1,7 code
SCSI rate
Max burst transfer	10 Mbytes/sec		20 Mbytes/sec
Seek time3
Average read	8.0 msec		8.0 msec
Average write	9.0 msec		9.0 msec
Disc rotation
RPM	7,200		7,200
Average latency	4.17 msec		4.17 msec

1Can also be operated according to SCSI-1 protocol.

2Standard factory units are formatted as follows:

512 data bytes per sector, 9 spare sectors per cylinder 1 cylinder at the inner track reserved for spares

3Not including on-board controller overhead.