Barracuda 7200.7 Serial ATA Product Manual, Rev. N 7
2.6 Seek time
Seek measurements are taken with nominal power at 25°C ambient temperatur e. All times are measured using
drive diagnostics. The specifications in the table below are def ined as follows:
• Track-to-tr ack seek time is an average of all possible single-tr ack seeks in both directions.
• Average seek time is a true statistical random average of at lea st 5,000 measuremen ts of seeks between
random tracks, less overhead.
*Measured in performance mode
Note. These drives are designed to consistently meet the seek times r epresented in this manual. Physical
seeks, regardless of mode (such as track-to-track and average), are expec ted to meet the noted
values. However, due to the manner in which these drives are formatted, benchmark tes ts that
include command overhead or measure logical see ks may produce results that va ry from these
specifications.
2.7 Start/stop times2.8 Power specifications
The drive receives DC power (+5V or +12V) through a native SATA power connector. See Figure 4 on page 20.
2.8.1 Power consumption
Power requirements for the drives are listed in the table on page 9. Typical power measur ements are based on
an average of drives tested, under nominal conditions, u sing 5.0V and 12.0V input voltage at 25°C ambient
temperature.
• Spinup power
Spinup power is measured from the time of power-on to the time that the drive spind le reaches operatin g
speed.
• Seek mo de
During seek mode, the read/write actuator arm moves toward a specific positi on on the disc surface and
does not execute a read or write operation. Servo electronics are active. S eek mo de power r epresen ts the
worst-case power consumption, using only random seeks with r ead or wr ite l atency ti me. T his m ode is not
typical and is provided for worst-case information.
• Rea d/write power and current
Read/write power is measured with the heads on track, based on a 16-sector wri te followed by a 32-msec
delay, then a 16-sector read followed by a 32-msec delay.
Table 3: Typical seek times
*Typical seek times (msec) Read Write
Track-to-track <1.0 <1.2
Average 8.5 9.5
Average latency 4.16 4.16
Power-on to Ready (sec) 10 (max)
Standby to Ready (sec) 10 (max)
Ready to spindle stop (sec) 10 (max)