# Remote Wake-Up

- About Remote Wake-up

- Physical Installation Issues

- BIOS Issues

- Operating System Settings

## About Remote Wake-up

The ability to remotely wake computers is an important development in computer management. This feature has evolved over the last few years from a simple remote power-on capability to a complex system interacting with a variety of device and operating system (OS) power states.
Wake on Magic Packet
In early implementations of Remote Wake-up, the computer could be started from a power-off state by sending a Magic Packet*. A Magic Packet is an Ethernet packet that contains an adapter’s MAC address repeated 16 times in the data field. When an adapter receives a Magic Packet containing its own MAC address, it activates the computer’s power. This enables network administrators to perform off-hours maintenance at remote locations without sending a technician out.

This early implementation required a computer that was equipped with a standby power supply and had the necessary circuitry to allow the remote power control. These computers were typically equipped with a feature named APM (Advanced Power Management). APM provided BIOS-based power control.

ACPI
Newer computers feature ACPI (Advanced Configuration and Power Interface), which extends the APM concept to enable the OS to selectively control power. ACPI supports a variety of power states. Each state represents a different level of power, from fully powered up to completely powered down, with partial levels of power in each intermediate state. Power states include:

Power State | Description
S0 | On and fully operational
S1 | System is in low power mode (sleep mode). The CPU clock is stopped, but RAM is powered on and being refreshed.
S2 | Similar to S1, but power is removed from the CPU.
S3 | Suspend to RAM (standby mode). Most components are shutdown. RAM remains operational.
S4 | Suspend to disk (hibernate mode). The memory contents are swapped to the disk drive and then reloaded into RAM when the system is awakened.
S5 | Power off

Some newer ACPI aware operating systems, such as Microsoft Windows* 98 SE, Windows Me, Windows 2000 and Windows XP*, only support remote wake-up from standby or hibernate mode (S3 and S4). Remote wake can be initiated by a variety of user selectable packet types and is not limited to the Magic Packet format. For more information about supported packet types, see the operating system settings section.

## Physical Installation Issues

Slot
Some motherboards will only support remote wake-up (or remote wake-up from S5 state) in a particular slot. For example, the Intel® Desktop Board D815EPEA2 will only support remote wake-up from an S5 state if the adapter is plugged into PCI slot 2. It will, however, support remote wake-up from standby from any slot. See the documentation that came with your system or motherboard for details on remote wake-up support.
Power
Intel PRO/1000 Desktop adapters are 3.3 volt, but will work in a 5-volt slot also. They are keyed to fit either type of slot.

If your remote wake-up enabled computer is compliant to PCI specification 2.2, then it does not require the 3-pin cable for remote wake-up. In these computers, the 3.3 volt standby supply must be capable of supplying at least 0.2 amps for each Intel PRO adapter installed. You may need to contact your computer manufacturer to verify the standby current rating. Turning off the remote wake up capability on the adapter using the IBAUTIL utility reduces the power draw to around 50 milliamps (.05 amps) per adapter.

## BIOS Issues

There are various settings in the computer BIOS that may need to be configured before remote wake-up will work.

Many ACPI computers can be configured to work in APM mode. Check your BIOS settings to determine which mode the computer is operating in.

In both APM and ACPI computers, you may find settings for Wake on LAN* under the Power Control area and titled Wake on LAN and/or Wake on PME. Wake on LAN setting refers to wake up events received through the 3-pin header cable. Wake on PME refers to wake up events received through the PCI bus. To enable remote wake-up, you should enable the setting that corresponds to the your adapter connection (e.g. set Wake on LAN to enable if you are using the WOL cable).

In ACPI computers operating in ACPI mode, if you are using an ACPI aware OS (such as Windows 2000), and wish to be able to power up the system from a power off state, look for an ACPI specific setting such as Wake on LAN from S5 and enable it.

## Operating System Settings

Microsoft Windows Products
Microsoft Windows NT is not ACPI capable. Some settings will not be available in these operating systems. See also the Other Operating Systems section below.

Microsoft Windows 98 SE, Windows Me, Windows 2000 and Windows XP are ACPI capable. These operating systems do not support wake from S5 state, only from standby. However, in some ACPI capable computers, the BIOS may have a setting that allows you to wake from an S5 state anyway. If there is no support for wake from S5 state in your BIOS settings, then you will be limited to wake from standby when using these operating systems in ACPI computers.

In the advanced settings for some adapters, there is a setting titled Enable PME. To explicitly allow wake up with a Magic Packet from shutdown under APM power management mode, set this to Enable. See Intel® PROSet help for more details.

In ACPI capable versions of Windows, the advanced settings will also include a setting titled Wake on Settings. This controls the type of packets that will wake up the system from standby. Click the Help button in Intel PROSet for a complete explanation.

In ACPI computers running ACPI aware operating systems (such as Windows 2000), make sure the wake on standby option is enabled. To enable wake on standby, open the Device Manager and then navigate to the adapter properties tab Power Management. The setting allow this device to bring the computer out of standby should be checked.

Other Operating Systems
In operating systems that do not support remote wake-up technology, you can still use the Magic Packet method of remotely powering up a computer. When the computer is first powered on, the Intel® Boot Agent configuration utility can be invoked by entering CTRL-S when the Boot Agent prompt appears on the screen. The configuration program has a parameter setting titled Legacy OS Wakeup Support. If this setting is enabled, the Boot Agent will pre-condition the adapter to respond to a Magic Packet wake up event. This allows remote wake-up in operating systems that do not support it.

| NOTE: The Legacy OS Wakeup Support feature was not available in early versions of the Intel® Boot Agent. To update your Boot Agent to the latest version, download 100PBOOT.EXE from support.intel.com and follow the included instructions.

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