DSL activity light blinking while idle - W2K

[Drewman444]

I have four PCs on my home network (all W2K), all connected to a Linksys router and then a DSL modem. While all the machines are idle, the activity light on my modem is blinking non-stop, but it stops when I disable the NIC card on a certain machine. The others don't cause the blinking when they are idle. Spyware? How do I find out what is causing it, and how do I stop it? THANKS!

[coleslaw]

If you install firewall software such as ZoneAlarm, it should tell you which applications are trying to access the network. Also, download and run AdAware to get rid of the spyware that you suspect in on this system.

[Jeffbx]

Could be a bad NIC - some just spew garbage when they go bad.

Could also be a virus - run a scanner on that PC!