DSL working on one computer not other, help

About 3 months ago I had comcast, but moved and now I’m just getting internet again, AT&T DSL… I’ve tried going through tech support with my router and modem companies, netgear and AT&T, and they just said its not the router or modem, its my computer, and I couldn’t even get close to getting help from microsoft. I use XP. For my local area connection it just says limited or no connectivity, and keeps giving me the 169.254.209.164 IP address. Is there something I’m not doing or seeing ? Do I need to give more information on my problem ?