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ACPI
The Altos R700 server board supports the Advanced Configuration and Power Interface (ACPI) as defined by the ACPI 2.0 specification. An ACPI aware operating system can put the system into a state where the hard drives spin down, the system fans stop, and all processing is halted. However, the power supply will still be on and the processors will still be dissipating some power, so the power supply fans will still run.
The Altos R700 server board supports sleep states s0, s1, s4, and s5:
•s0: Normal running state.
•s1: Processor sleep state. No context will be lost in this state and the processor caches will maintain coherency.
•s4: Hibernate or Save to Disk: The memory and machine state are saved to disk. Pressing the power button or other wakeup event will restore the system state from the disk and resume normal operation. This assumes that no hardware changes have been made to the system while it was off.
•s5: Soft off: Only the RTC section of the CSB and the BMC are running in this state. No context is saved by the OS or hardware.
Caution: The system is off only when the AC power cord is disconnected.
