Computer Sucking Up Bandwidth

I'm sharing an internet connection with my step-dad's computer. For some reason after his computer had been running for a while (couple hours) it starts to use up huge amounts of bandwidth. When I check the status of his connection it says he's sending and receiving millions of packets. This is when the computer is idle and no programs are running.

I've run a Norton scan, Spybot scan, and Adaware scan but nothing seems to be wrong. Also, I've posted the HijackThis log on TSG forums and it's apparently very clean.

Restarting the computer takes care of the problem. Unfortunately, I can't always restart the computer as I wish because it's not mine and there's sometimes programs running and whatnot that I wouldn't want to interrupt.

I don't know where to go from here??

Any help is appreciated!

-Cap'n Bob

 

Stupid question, but...you are sharing the connection how? A router? What kind/type/etc?

 

This maybe of some help....
http://www.webmasterworld.com/forum23/2836.htm