Seagate BARRACUDA ST11950N/ND/W/WD - Manual (Page 17)

ST11950 and ST12550 Installation Guide, Rev. D 15
Characteristics ST12550N/ND ST12550W/WD
Interface Fast SCSI-2 1 Fast & Wide SCSI-2 1
Multi-seg. cache 1,024 Kbytes 1,024 Kbytes (W)
512 Kbytes (WD)
Capacity
Unformatted 2,572 Mbytes 2,572 Mbytes
Formatted 2 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 time 3
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
1 Can also be operated according to SCSI-1 protocol.
2 Standard 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
3 Not including on-board controller overhead.