Desktop Board Description
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Table 10 lists the power states supported by the board along with the associated system power
targets. See the ACPI specification for a complete description of the various system and power
states.
Table 10. Power States and Targeted System Power
Global States
Sleeping States
CPU States
Device States
Targeted System
Power
(Note 1)
G0 - working state
S0 – working
C0 - working
D0 - working state
Full power > 30 W
G1 - sleeping state
S1 - CPU stopped
C1 - stop
grant
D1, D2, D3 - device
specification specific.
5 W < power < 30 W
G1 - sleeping state
S3 - Suspend-to-RAM
Context saved to RAM
No power
D3 - no power except for
wake up logic.
Power < 5 W
(Note 2)
G2/S5
S5 - Soft off. Context
not saved. Cold boot
is required.
No power
D3 - no power except for
wake up logic.
Power < 5 W
(Note 2)
G3 - mechanical off
AC power is
disconnected from
the computer.
No power to the
system.
No power
D3 - no power for wake
up logic, except when
provided by battery or
external source.
No power to the system
so that service can be
performed.
Notes:
1.
Total system power is dependent on the system configuration, including add-in boards and peripherals powered by the
system chassis’ power supply.
2.
Dependent on the standby power consumption of wake-up devices used in the system.
1.13.1.2.2
Wake Up Devices and Events
Table 11 lists the devices or specific events that can wake the computer from specific states.
Table 11. Wake Up Devices and Events
These devices/events can wake up the computer…
…from this state
Power switch
S1, S3, S5
RTC alarm
S1, S3, S5
LAN (S5 state requires a Wake on LAN technology connector)
S1, S3, S5
Modem S1,
S3
USB
S1, S3
PS/2 keyboard
S1, S3
PS/2 mouse
S1, S3
PME#
S1, S3
1.13.1.2.3
Plug and Play
In addition to power management, ACPI provides controls and information so that the operating
system can facilitate Plug and Play device enumeration and configuration. ACPI is used only to
enumerate and configure board devices that do not have other hardware standards for enumeration
and configuration. PCI devices on the board, for example, are not enumerated by ACPI.