8 Barracuda 7200. 7 Serial ATA Product Manual, Rev. N
• Operating power and current
Operating power is measured using 40 percent random seek s, 40 percent read/write mode (1 write for each
10 reads) and 20 percent drive idle mode.
• Idle mode power
Idle mode power is measured with the drive up to speed, with servo electronics active and with th e heads in
a random track location.
• Standby mode
During Standby mode, the drive accepts commands, but the drive is not s pinning , an d the servo and r ead/
write electronics are in power-down mode.
[1] NCQ may not be enabled during power measurements.
[2] During periods of drive idle, some offline activity may occur according to the S. M.A.R.T. specification,
which may increase acoustic and power to operationa l levels.
Table 4: DC power requirements (example of 160GB models supporting NCQ[1])
Power dissipation (watts) Average
(watts, 25° C) 5V typ
amps 12V typ amps
Spinup — — 2.8 (peak)
Idle 7.5 0.487 0.422
Idle (with offline activity) [2] 9.3 0.875 0.41
Operating (40% r/w, 40% seek, 20% inop.) 12.0 0.631 0.737
Seeking 12.5 0.405 0.873
Standby/Sleep 1.0 0.185 0.006
Table 5: DC power requirements (example of 160GB and 200GB models not supporting NCQ)
Power dissipation (watts) Average
(watts, 25° C) 5V typ
amps 12V typ amps
Spinup — — 2.8 (peak)
Idle 7.5 0.482 0.424
Idle (with offline activity) [2] 9.3 0.587 0.53
Operating (40% r/w, 40% seek, 20% inop.) 12.1 0.638 0.739
Seeking 12.5 0.412 0.87
Standby/Sleep 2.0 0.367 0.014