On To Off (Os Absent); On To Off (Os Present); System Sleep States - Intel SE7525GP2 Technical Manual

Intel® Server Boards SE7320SP2 and SE7525GP2
4.9.5

On to Off (OS absent)

The SCI interrupt is masked. The firmware polls the power button status bit in the ACPI
hardware registers and sets the state of the machine in the chipset to the OFF state. The
mBMC monitors power state signals from the chipset and de-asserts PS_PWR_ON to the
power supply. As a safety mechanism, the mBMC automatically powers off the system in 4-5
seconds if the BIOS fails to service the request.
4.9.6

On to Off (OS present)

If an operating system is loaded, the power button switch generates a request (via SCI) to the
OS to shutdown the system. The OS retains control of the system and OS policy determines
what sleep state (if any) the system transitions into.
4.9.7

System Sleep States

The platform supports the following ACPI system sleep states:
ACPI S0 (working) state
ACPI S1 (sleep) state
ACPI S4 (suspend to disk) state
ACPI S5 (soft-off) state
The platform supports the following wake up sources in an ACPI environment. As noted above,
the OS controls the enabling and disabling of these wake sources.
Devices that are connected to all USB ports, such as USB mice and keyboards can
wake the system up from the S1 sleep state.
PS/2 keyboards and mice can wake up the system from the S1 sleep state.
Both serial ports can be configured to wake up the system from the S1 sleep state.
PCI cards, such as LAN cards, can wake up the system from the S1 or S4 sleep state.
Note that the PCI card must have the necessary hardware for this to work.
As required by the ACPI Specification, the power button can always wake up the system
from the S1 or S4 state.
Revision 4.0
System BIOS
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