User Manual

Constellation.2 Serial ATA Product Manual, Rev. G 12

2.4 Recording and interface technology

2.5 Physical characteristics

Note. Refer to Figure 6, page 30 for detailed mounting configuration dimensions.

2.6 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 5,000 measurements of seeks between random

tracks, less overhead.

*Measured in performance 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 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.

All models

Interface Serial ATA (SATA)

Recording method Perpendicular

Recording density, KBPI (Kb/in max) 1544

Track density, KTPI (Ktracks/in avg) 270

Areal density (Gb/in

avg) 417

Spindle speed (RPM) (± 0.2%) 7200

Internal data transfer rate (Mb/s max) 1304

Sustained data transfer rate (MB/s max) 115

I/O data-transfer rate (MB/s max) 600

Weight: (maximum)

1TB models

500GB models

250GB models

200 g (0.441 lb)

183 g (0.403 lb)

179 g (0.395 lb)

Cache buffer 64 MB (65,536 KB)

*Typical seek times (ms) Read Write

Track-to-track 0.23 0.44

Average 7.5 8.5

Full Stroke 17.06 18.08

Average latency: 4.16