Power States And Targeted System Power - Intel D845HV Technical Product Specification

1.14.1.1 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 9 lists the power states supported by the D845HV and D845WN boards along with the
associated system power targets. See the ACPI specification for a complete description of the
various system and power states.
Table 9.

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.
Processor
States Device States
C0 – working D0 – working
state.
C1 – stop D1, D2, D3 –
grant device
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.
Product Description
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 so
that service can be
performed.
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