Onboard LAN powered when PC is shutdown

[Messerschmitt]

Hey guys. Any clue why my LAN would stay powered when the PC is off? Would it have something to do with Windows 7? In device manager I have unticked "Allow this device to wake up computer"

Basically when I shut it down, my switch LED turns off for about 2 seconds, then comes on again. If I would kill the PC power (turn PSU off), switch LED would turn off, and will stay off until I start the computer again.

[jaclaz]

That is "by design".

Any ATX powered PC (anything built in the last - say - 15 years) would normally behave like that, some BIOSes may allow to NOT power the network card, but normally it is powered when the PC is "off".

Basically an ATX power supply is like having TWO power supplies inside, the "main one" is switched on when you switch the PC ON, the second (very small power one) will always be on as long as it is connected to mains (some but not all have a mechanical switch on the back that allows switching it "really" off).

http://en.wikipedia.org/wiki/ATX

http://wiki.answers.com/Q/What_are_the_differences_between_AT_and_ATX_power_supply

The network card is normally powered even when the PC is off, to allow the wake on lan, as well most BIOS allow to switch the PC on from a press of a key on the keyboard or a mouse click, so these are also powered.

jaclaz

[Messerschmitt]

Ah, I had a feeling this would be the case. My (very old) PC, laptop when plugged in (ethernet cable) and NAS (synology) not keeping the LED on on my switch made me think otherwise.

Any chance to disable that, just an FMI.

Edited February 8, 2013 by Messerschmitt

[uid0]

There could be wake-on-lan options in the network card driver, or in the bios.

Sometimes they get creative with the descriptions, like PME (Power Management Events) or "deep sleep".

Or there is always the wall switch...

[jaclaz]

...and - as always - there can be n shades of gray instead of Black/White On/Off :

http://support.dell.com/support/topics/global.aspx/support/kcs/document?c=us&l=en&s=gen&docid=DSN_F78F568BBB1BC1A0E030030ABD625AEA&isLegacy=true&DoNotRedirect=y

Every BIOS has it's more or less clear "wording", this is a good overview on WOL (Wake on Lan):

http://www.i-mentalist.com/support/faq/wol/

where you can find more possible "keywords".

jaclaz

[Messerschmitt]

Under windows, I have un-checked "Allow this device to wake the computer"

Under BIOS, I have disabled anything that references wake-on-lan.

I don't really have a problem as I can live with it. Thanks for all the info