Seagate Video 2.5 HDD Product Manual, Rev. J (Draft 1)
9
Drive Specifications
2.2
Physical organization
2.3
Recording and Interface Technology
2.4
Physical Characteristics
2.5
Seek 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 5000 measurements of seeks between random tracks, less overhead.
Drive model
Read/write heads
Number of disks
ST500VT000 and ST500VT001
2
1
ST320VT000
ST250VT000
Interface
Serial ATA (SATA)
Recording method
Perpendicular
Recording density
1875 Kb/in
Track density
375 ktracks/in avg
Areal density
670 Gb/in
2
avg
Spindle speed
5400 RPM +/- 0.2%
Sustained data transfer rate
100 MB/s max
I/O data-transfer rate
600 MB/s max
All models
Height
6.8 +/- 0.2 mm (0.268 +/-.008 in)
Width
69.85 +/- 0.25 mm (2.750 +/- 0.010 in)
Length
100.35 +0.20 / -0.25 mm (3.951 +0.008 / -0.010 in)
Typical weight
<95 g (0.209 lb)
ST500VT000, ST320VT000
and ST250VT000
Cache buffer
16 MB (16,192 KB)
ST500VT001
32MB (32,384 KB)
Table 2
Typical seek times
Typical seek times (ms)
Read
Track-to-track
1.5
Average
12.0
Average latency
5.6
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 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 specifications.
