Dear Valued Linksys Customer, Thank you for contacting Linksys Customer Support. Please try to connect your computer that is running at 100Mbps to the other ports of your router. And check if it will run properly with your router at 100Mbps and if the led lights of 100 are illuminated. If you have further questions, please contact us at (800) 326-7114 or send us an email at http://www.linksys.com/~support so that we may further assist you. Please use this phone number given as reference for future support calls. Sincerely, Dino Miguel R. Santos Product Support Representative Linksys If you are responding to this e-mail, please attach all previous correspondence as a point of reference.