Acpi; Wakeup Events - Intel SE7501BR2 - Server Board Motherboard Product Manual

ACPI

By using Advanced Configuration and Power Interface (ACPI), an ACPI-aware operating system
can place the system into a state in which the hard drives spin-down, the system fans stop, and all
processing is halted. In this state the power supply is still on and the processors still dissipate some
power, so the power supply fan and processor fans are still running.
NOTE
ACPI requires an operating system that supports this feature.
The server board supports sleep states S0, S1, S4, and S5. When the server board is operating in
ACPI mode, the operating system retains control of the system and the OS policy determines the
entry methods and wake-up sources for each sleep state – sleep entry and wake-up event
capabilities are provided by the hardware but are enabled by the operating system.
S0: Normal running state.
S1: DC Power remains on. The operating system saves the context and enters a low-power
state. The system can wake from the S1 state using a PS/2 keyboard, mouse, or USB device,
by pressing the power button press, or from a wakeup event.
S4: Hibernate or Save to Disk. The memory and machine state are saved to disk. Pressing the
power button or another wakeup event restores the system state from the disk and resumes
normal operation. This assumes that no hardware changes were made to the system while it
was off.
S5: Soft off. Only the RTC section of the chip set is running in this state.
CAUTION
The system is off only when the AC power is disconnected.

Wakeup Events

The SE7501BR2 system supports several wakeup events.
Wake on LAN
Wake on LAN allows system power to be activated through the network. If the system is in the S1
or S4 state, it can be turned on remotely by sending a specific packet to the remote system. The
system contains a configuration option that allows the on-board NICs to be enabled to wake the
system from a S4 or S5 sleep state, even if the operating system disabled Wake on LAN when it
powered down the system. This provides an option for users who want to use standard, but
non-secure, Wake on LAN capability for operations such as after-hours maintenance. Server
management features provide a secure system power-up, plus the ability to provide BIOS boot
option.
20 Intel Server Board SE7501BR2 Product Guide