Seagate ST31000525SV, ST2000VX002 manual Physical characteristics, Seek time, Start/stop times

2.5Physical characteristics

	2TB model	1TB models	500GB models	250GB model
Maximum height	26.1mm (1.028 in)	26.1mm (1.028 in)	19.98mm (0.787 in)	20.20 mm (0.794 in)
Maximum width	101.6mm (4.0 in)	101.85mm (4.010 in)	101.85mm (4.010 in)	101.85mm (4.010 in)
Maximum length	147.00mm (5.78 in)	146.99mm (5.787 in)	146.99mm (5.787 in)	146.99mm (5.787 in)
Typical weight	635g (1.39 lb)	677g (1.493 lb)	544 grams (1.199 lb)	380 grams (0.838 lb)
Cache buffer	64MB	32MB	16MB	16MB

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 ran- dom tracks, less overhead.

	2TB model		1TB and 500GB model		250GB models
Typical seek times (msec)*	Read	Write	Read	Write	Read	Write
Track-to-track	<0.5	<1.5	<0.5	<1.5	<1.0	<1.2
Average	<8.5	<9.5	<8.5	<9.5	<8.5	<9.0

*Measured in Seek mode.

Note. These drives are designed to consistently meet the seek times represented in this manual. Physical seeks, regardless of mode (such as track-to-track and average), are expected to meet the noted val- ues. However, due to the manner in which these drives are formatted, benchmark tests that include command overhead or measure logical seeks may produce results that vary from these specifications.

2.7Start/stop times

	2TB model	1TB and 500GB models	250GB models
Power-on to Ready (max)	<17s	<10s	<8s
Ready to spindle stop (max)	10s	12s	12s

Note. Start/stop measurements are taken with nominal power at 25°C ambient temperature.

SV35 Series SATA Product Manual, Rev. D 9