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1.16.1.1
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
G0 – working
state
G1 – sleeping
state
G1 – sleeping
state
G2/S5
G3 –
mechanical off
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
Sleeping States
States
S0 – working
C0 – working
S3 – Suspend to
No power
RAM. Context
saved to RAM.
S4 – Suspend to
No power
disk. Context
saved to disk.
S5 – Soft off.
No power
Context not saved.
Cold boot is
required.
No power to the
No power
system.
Product Description
Targeted System
Power (Note 1)
Device States
D0 – working
Full power > 30 W
state.
D3 – no power
Power < 5 W
except for
wake-up logic.
D3 – no power
Power < 5 W
except for
wake-up logic.
D3 – no power
Power < 5 W
except for
wake-up logic.
D3 – no power for
No power to the system.
wake-up logic,
Service can be performed
except when
safely.
provided by
battery or
external source.
(Note 2)
(Note 2)
(Note 2)
31
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