Constellation Serial ATA Product Manual, Rev. B
7
2.5
Physical characteristics
Maximum height
14.8 mm (0.583 inches)
Maximum width
70.0 mm (2.76 inches)
Maximum length
100.5 mm (3.957 inches)
Max weight
ST9500530NS
196 grams (0.43 lbs)
ST9160511NS
188 grams (0.41 lbs)
Cache buffer
32 Mbytes (32,768 kbytes)
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.
*Typical seek times (msec)
Read
Write
Track-to-track
0.5
0.7
Average
8.0
8.4
Full Stroke
17.4
17.9
Average latency:
4.16
*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.
2.7
Start/stop times
ST9500530NS
ST9160511NS
Power-on to Ready (sec)
20 (max)
Standby to Ready (sec)
6 (max)
4 (max)
Ready to spindle stop (sec)
20 (max)
