When I shut down Windows 7, my NIC remains active and the link status LED on the router remains lit. When I shut down Windows XP, it does not. Further, rebooting XP causes the NIC to shutdown as well, while rebooting Windows 7 leaves it active.
It is not a hardware configuration issue (eg WOL setting in BIOS—which for the record is disabled) because like I said, it does indeed turn off when XP is shut down. The issue is with Windows 7.
Yes, I have already changed the settings (figure 1) for the network card in Device Manager to disable all
Magic-Packet, etc. settings as well as checking the
Allow computer to turn off this device option in the Power Management tab. I have done this in both XP and 7. (The (default) Windows 7 drivers seem to have more options than the (again default) Windows XP drivers.)
I did find plenty of hits about this issue, but not surprisingly, most of them just said to turn WOL off (and yet a lot of the askers said they already did). Strangely enough, one person actually complained that their NIC stays on in Ubuntu but turns off in Windows 7. I have the opposite issue in 7.
I have set the standby state to S3 in the BIOS instead of S1 and also used
dumppo to set the minimum standby state to S3 in both XP and 7. Examining the power-setting differences (figure 2), I do not see anything relevant to the network adapter, so I am at a loss as to why 7 would force the NIC to remain active.
Update: Just to add to the confusion, I have noticed that when I put Windows 7 into standby/sleep mode, the link-LED turns off. So Windows 7 is capable of shutting the NIC off, and does so when put to sleep, but for some reason does not do so when shut down.
Figure 1: NIC driver settings in XP and 7
dumppo differences between XP and 7