Table 5. Effects Of Pressing The Power Switch; Table 6. Power States And Targeted System Power - Intel S875WP1LX Specification

Functional Architecture
Table 5 lists the system states based on how long the power switch is pressed, depending on
how ACPI is configured with an ACPI-aware operating system.
If the system is in this state...
Off
(ACPI S5 – Soft off)
On
(ACPI S0 – working state)
On
(ACPI S0 – working state)
Sleep
(ACPI S1 or S3 – sleeping state)
Sleep
(ACPI S1 or S3 – sleeping state)
3.6.1.1 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 6 lists the power states supported by the Server Board S875WP1-E along with the
associated system power targets. See the ACPI specification for a complete description of the
various system and power states.

Table 6. 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/G5 S5 – Soft off.
Context not saved.
Cold boot is
required.
24

Table 5. Effects of Pressing the Power Switch

...and the power switch is
pressed for
Less than four seconds
Less than four seconds
More than four seconds
Less than four seconds
More than four seconds
Processor
States
C0 – working
C1 – stop
grant
No power
No power
No power
...the system enters this state
Power-on
(ACPI S0 – working state)
Soft-off/Standby
(ACPI S1 or S3 – sleeping state)
Fail safe power-off
(ACPI S5 – Soft off)
Wake-up
(ACPI S0 – working state)
Power-off
(ACPI S5 – Soft off)
Targeted System
Device States Power (Note 1)
D0 – working state. Full power > 30 W
D1, D2, D3 – 5 W < power < 52.5 W
device specification
specific.
D3 – no power Power < 5 W (Note 2)
except for wake-up
logic.
D3 – no power Power < 5 W (Note 2)
except for wake-up
logic.
D3 – no power Power < 5 W (Note 2)
except for wake-up
logic.
S875WP1-E TPS
Revision 4.0