Intel OCPRF100 MP - Manual (Page 79)

OCPRF100 MP Server System Technical Product Specification
Revision 1.0
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The system supports the S1, S4 OS, and S5 sleep states. It also supports Wake-on-LAN* from
the S1 and S4 states.
After the operating system sends the command to switch to ACPI mode, the power button acts
as a sleep button and a power button. If the button is pressed for less than four seconds, the sys-
tem enters a sleep state determined by the operating system. If it is pressed for more than four
seconds, the system powers down to the S5 state.
S1 Sleep State. The system enters the S1 sleep state when the power button is pressed
momentarily or when the operating system directs it to enter S1. The S1 sleep state retains the
system context; all processors’ caches, memory, and chip set devices retain their state informa-
tion. Only the power button and power management events (Wake-on-LAN) can wake the sys-
tem from S1.
S4 Sleep State. The system enters the S4 state when the power button is pressed (if configured
for hibernation) or when the hibernate option is chosen in the shutdown menu. If the operating
system supports save-to-disk, it stores the system context to hard disk before powering down.
When the system powers on, the operating system restores all processes from the disk. When
the system awakens, BIOS performs a normal boot; BIOS does not participate in saving and
restoring the system context.
S5 Sleep State. The system powers down without saving context.
6.2.2 Boot Devices and Peripherals
The system BIOS supports a wide range of peripherals and boot devices. The system can boot
an operating system from a floppy, an IDE device, a SCSI device, a network card, or an I
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O
device. Bootable CD-ROMs are supported in emulation and nonemulation modes.
The system BIOS supports the following specifications:
• BIOS Boot Specification, Version 1.01.
• El Torito CD-ROM Boot Specification, Version 1.0.
• Intelligent I/O (I
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O) Architecture Specification, Revision 1.0.
• Universal Serial Bus (USB) Specification, Revision 1.0.
Legacy USB devices are not supported by BIOS, but nothing in BIOS precludes support by an
operating system. A USB-aware operating system can enable the USB functionality.
Ordinarily, the system BIOS boots from the first device detected in its scan order. If adapters con-
form to the BIOS Boot Specification, the boot device can be selected without changing the place-
ment of the adapter cards.
I
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O defines a standard architecture for intelligent I/O. This is an approach to I/O in which low-
level interrupts are handled by specially designed I/O processors which communicate by passing
messages. Although the OCPRF100 MP server system does not include any built-in I
2
O devices,