Power States And Targeted System Power - Intel BOXD945GBOLKR Technical Product Specification

Intel Desktop Board D945GBO Technical Product Specification
1.13.1.1 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 7 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 7.

Power States and Targeted System Power

Global States Sleeping States
G0 – working S0 – working
state
G1 – sleeping S1 – Processor
state stopped
G1 – sleeping S3 – Suspend to
state RAM. Context
saved to RAM.
G1 – sleeping S4 – Suspend to
state disk. Context
saved to disk.
G2/S5 S5 – Soft off.
Context not saved.
Cold boot is
required.
G3 – No power to the
mechanical off system.
AC power is
disconnected
from the
computer.
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 One-Watt Standby
In 2001, the U.S. government issued an executive order requiring a reduction in power for
appliances and personal computers. This board meets that requirement by operating at 1 W (or
less) in S5 (Standby) mode. One-Watt operation applies only to the S5 state when the computer is
turned off, but still connected to AC power. One-Watt operation does not apply to the S3 (Suspend
to RAM) or S4 (Suspend to disk) states.
Newer energy-efficient power supplies using less than 0.5 W (in Standby mode) may also be
needed to achieve this goal.
38
Processor
States Device States
C0 – working D0 – working state.
C1 – stop D1, D2, D3 – device
grant specification
specific.
No power D3 – no power
except for wake-up
logic.
No power D3 – no power
except for wake-up
logic.
No power D3 – no power
except for wake-up
logic.
No power D3 – no power for
wake-up logic,
except when
provided by battery
or external source.
Targeted System
(Note 1)
Power
Full power > 30 W
5 W < power < 52.5 W
(Note 2)
Power < 5 W
(Note 2)
Power < 5 W
(Note 2)
Power < 5 W
No power to the system.
Service can be
performed safely.