Seagate ST31000524AS Recording and interface technology, Physical characteristics, Seek time

www.seagate.com Drive Specifications

2.4Recording and interface technology

Interface	Serial ATA (SATA)
Recording method	Perpendicular
Recording density (kbits/inch max)	1413
Track density (ktracks/inch avg)	236
Areal density (Gbits/inch2 avg)	329
Spindle speed (RPM)	7,200 ± 0.2%
Internal data transfer rate (Mb/s max)	1695
Sustained data transfer rate (MB/s max)	125
I/O data-transfer rate (MB/s max)	600

2.5Physical characteristics

Maximum height
1000 and 750GB models	26.1mm / 1.028 in
500, 320, 250 and 160GB models	19.98mm / 0.787 in
Maximum width	101.6mm / 4.000 (+ 0.010 in)
Maximum length	146.99mm / 5.787 in
Typical weight
1000 and 750GB models	622g / 1.371 lb
500, 320, 250 and 160GB models	415g / 0.915 lb
Cache buffer
1000 and 750GB models	32MB (32,768kb)
500 and 320GB models	16MB (16,384kb)
250 and 160GB models	8MB (8192kb)

2.6Seek time

Seek measurements are taken with nominal power at 25°C ambient temperature. All times are measured using drive diagnostics. The specifications in the table below are defined as follows:

•Track-to-track seek time is an average of all possible single-track seeks in both directions.

•Average seek time is a true statistical random average of at least 5,000 measurements of seeks between random tracks, less overhead.

Typical seek times (ms)	Read		Write
Track-to-track	1.0		1.2
Average	8.5		9.5
Average latency		4.16

Barracuda SATA Product Manual, Rev. B 17