Operation With Power Management Modes - Hitachi IC25N040ATCS04-0 - Travelstar 40GN 40GB UDMA/100 4200RPM 2MB 2.5" IDE Hard Drive Specifications

11.8.6 S.M.A.R.T. operation with power management modes
The device saves attribute values automatically on every head unload timing except the emergency un-
load, even if the attribute auto save feature is not enabled. The head unload is done not only by Standby,
Standby Immediate, or Sleep command or Hard Reset, but also by the automatic power saving functions
like ABLE-3 or Standby timer. So basically it is not necessary for a host system to enable the attribute
auto save feature, when it utilizes the power management. If the attribute auto save feature is enabled,
attribute values will be saved after 30minutes passed since the last saving, besides above condition.
Hitachi Travelstar 60GH & 40GN hard disk drive specifications
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