User Guide

Introduction of the BIOS 3-31
User’s Manual
System States and Power States
Under ACPI, the operating system directs all system and device power state transitions. The
operating system puts devices in and out of low-power states based on user preferences and
knowledge of how devices are being used by applications. Devices that are not being used
can be turned off. The operating system uses information from applications and user settings
to put the system as a whole into a low-power state.
Table 3-6-1: Wake Up Device and Events
The table below describes which devices or specific events can wake the computer from
specific states.
These device/events can wake up the
computer…… ……from this state
Power switch Sleeping mode or power off mode
RTC alarm Sleeping mode or power off mode
LAN Sleeping mode or power off mode
Modem Sleeping mode or power off mode
IR command Sleeping mode
USB Sleeping mode
PS/2 keyboard Sleeping mode
PS/2 mouse Sleeping mode
Table 3-6-2: Effect of Pressing the Power Switch
If the system is in this
state……
……and the power switch
is pressed for ……the system enters this
state
Off Less than four seconds Power on
On More than four seconds Soft off/Suspend
On Less than four seconds Fail safe power off
Sleep Less than four seconds Wake up
Power Management:
This item allows you to select the type (or degree) of power saving and is directly related to
the following modes:
1. Doze Mode
2. Standby Mode
3. Suspend Mode
4. HDD Power Down
There are three options for power management, three of which have fixed mode settings: