Camille said:
Assume I am sitting in front of a computer (from a friend). How can I find out if the hardware
supports Wake-on-lan?
Is this feature dependent from the BIOS of the motherboard or from the network card?
Camille
These are the ingredients for Wake on LAN. We'll start
with the physical layer first.
*******
On older computers, there used to be a WOL header on the motherboard. You
would add a NIC card to a PCI slot, then run a three wire cable from the
NIC card WOL header, to the motherboard WOL header.
Newer systems use a different scheme. The WOL header is gone. A signal
called PME on the PCI bus, is available for hardware seeking to wake
the computer. You can buy NIC cards compatible with this "PME on PCI" scheme,
and when doing so, the three wire cable is no longer needed.
Generally, those two schemes are mutually exclusive. You wouldn't mix a
NIC card with three pin WOL header, with a modern motherboard, because
the card may not be driving the PME signal on the PCI bus.
*******
In the BIOS, you go to the power management setting, and enable
"Wake on PME". PME stands for Power Management Event. It is basically
an interrupt of sorts, to wake the computer. PCI Express may have
its own wake up signal, with a different name. It would be in the same
BIOS setup page as the Wake on PME.
*******
Next, comes the NIC specific settings. Go to the Device Manager.
Do "Properties" on the NIC device. Look at the Power Management tab.
Enable the setting:
"Allow this device to bring the computer out of standby"
That allows waking as long as standby voltage is present on the NIC chip.
Then, under the Advanced tab, look for a setting with "Wake" in the name.
Each NIC could be different. My current NIC says "Wake up Type" for
example. One of the menu options for "Wake Up Type" is "Magic Packet",
which would be the classical wakeup mechanism.
On the one hand, looking at the Advanced Tab would seem to tell you
what you seek to know. But if the rest of the infrastructure isn't
enabled, it isn't going to work.
When the computer is in Standby, you should see a LED glowing on the
NIC interface connector. Some NIC connectors are cheap enough, they
have no visual indicators at all. If there are LEDs present, they
give you a quick confirmation that the NIC card (or built-in NIC
chip) has a standby voltage source. If you see no evidence the NIC
interface is powered, when in standby, that is going to severely
reduce the odds of it waking up.
Paul