Seagate BARRACUDA 7200.11 - Manual (Page 15)

Barracuda 7200.11 Serial ATA Product Manual, Rev. B 9
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 5,000 measurements of seeks between
random tracks, less overhead.
*Measured in performance mode.
**Measured in quiet 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.
Maximum height
1000 & 640 GB models 26.1 mm (1.028 inches)
320 & 160 GB models 20.17 mm (0.794 inches)
Maximum width 101.6 mm (4.000 +/- 0.010 inches)
Maximum length 146.99 mm (5.787 inches)
Typical weight
1000 GB models 677 grams (1.493 lbs)
640 GB models 543 grams (1.199 lbs)
320 & 160 GB models 368 grams (0.811 lbs)
Cache buffer
ST31000333AS & ST3640323AS 32 Mbytes (32,768 kbytes)
ST3320613AS 16 Mbytes (16,384 kbytes)
ST3320813AS and ST3160813AS 8 Mbytes (8,192 kbytes)
Typical seek times (msec) Read Write
Track-to-track <1.0 <1.2
Average (1000 & 640 GB models) <8.5 <9.5
Average (320 & 160 GB models) <11.0 <12.0
Average latency: 4.16