This policy setting specifies the period of inactivity before Windows turns off the hard disk.If you enable this policy setting you must provide a value in seconds indicating how much idle time should elapse before Windows turns off the hard disk.If you disable or do not configure this policy setting users can see and change this setting.
Policy path:
System\Power Management\Hard Disk Settings
Scope:
Machine
Supported on:
At least Windows Vista
Registry settings:
HKLM\Software\Policies\Microsoft\Power\PowerSettings\6738E2C4-E8A5-4A42-B16A-E040E769756E!DCSettingIndex
Filename:
Power.admx