I've never in my life heard of a dial up modem connecting to cable. They're quite different. When you connect to the net, do you hear the computer dial up? Or are you permanently connected the moment you turn your computer on?

Motorolla is a start. Do you see any model no.'s on it like: BR700, SBG900, WR850G, etc.?

Also back to your OS? Do you know which one?