Constellation ES.1 Serial ATA Product Manual, Rev. B
7
3.5
Physical characteristics
Weight: (maximum)
2TB models
710g (1.565 lb)
1TB models
640g (1.411 lb)
500GB models
610g (1.345 lb)
Cache buffer
64MB (64,768KB)
3.6
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 5000 measurements of seeks between
random tracks, less overhead.
*Typical seek times (ms)
Read
Write
Track-to-track
0.5
0.8
Average
<8.5
<9.5
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.
3.7
Start/stop times
2TB models
1TB models
500GB models
Power-on to Ready (sec)
15 (max)
10 (max)
7 (max)
Standby to Ready (sec)
15 (max)
10 (max)
7 (max)
Ready to spindle stop (sec)
20 (max)
