Cable Modem Networked

I have a new Dell desktop computer and a new Compaq Laptop. They both came with preinstalled ethernet cards. I have had the Dell hooked up to the cable modem and decided that I would network them so my roommate and I could both use the Highspeed connection. I bought a Hub and cables and followed instructions to the letter on installing them. The service works for the desktop but not the laptop. After some simple troubleshooting I decided to plug the cable modem directly to the laptop…nothing happend. I configerd the internet setting to be the same as the desktop and still nothing. Am I missing something or what?