XP Media Center Clogging Internet Connection

I continue to have issues with my Gateway 610XL Media
Center PC where the internet connection gets clogged and I
am forced to disconnect the ethernet connection and
reboot. I have tried running Ad-aware, disabling all start
programs in MS Config, and the 'clogging' still happens
even when I am not roaming the internet (but the PC is on
and connected via cable modem). I have tried disabling the
Media Center TV guide, but it still seems to continue. I
ran a recent virus check, no virus's. I am trying to
determine what other services may be running that may be
causing the problem.