My Dimension 4600 fried last week, and I replaced the motherboard today. Everything went smoothly, except I have no internet access. XP says "network cable is unplugged" even though it's clearly not. The cable & connection have been tested and both are working (just tested on this laptop) but in the desktop I get nothing. The light in back that used to light up when I plugged in the cable no longer does so. Does this mean the new (well, refurbished) motherboard's onboard network port is shot?