Seagate ST980829A manual Recording and interface technology, Physical characteristics, Seek time

2.5Recording and interface technology

Technology	Specification
Interface	Parallel ATA
Recording method	RLL 0,11
Recording density BPI (bits/inch typical)	778k
Track density TPI (tracks/inch typical)	126k
Areal density (Mbits/inch2 max)	98.2
Spindle speed (RPM) (± 0.2%)	4,200 RPM-class performance (actual spin speed: 5,400 RPM)
Internal data-transfer rate OD (Mbytes/sec max)	37
I/O data-transfer rate (Mbytes/sec max)	100 (Ultra DMA mode 5)
Interleave	1:1
Cache buffer	8 Mbytes (8,184 kbytes)

2.6Physical characteristics

Height	(mm)	9.5 +/-0.2
	(inches)	0.374	+/-0.008
Width	(mm)	69.85	+/-0.25
	(inches)	2.750	+/-0.010
Length	(mm)	100.2	+/-0.25
	(inches)	3.945	+/-0.010
Typical weight	(grams)	100
	(pounds)	0.22

2.7Seek time

Seek measurements are taken with nominal power at 25°C ambient temperature. All times are measured using drive diagnostics. The specifications 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 (msec)	Read	Write
Track-to-track	1.5	2.0
Average	12.5	14.5
Full-stroke	22.0	24.0
Average latency	5.56	5.56

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 or exceed the noted values. 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 speci- fications.

8 Momentus 4200.2 Product Manual, Rev. C