Killing my network when trying to connect?

[okayplayer]

Hey guys, I could use some help.

I just picked up a spiffy new Lenovo Ideapad notebook and am having some issues connecting to my home network. I am running a DLink wireless router which I haven't had any problems with before. My new notebook detects the network, but while connecting to it, I lose internet connectivity and have to reboot my router/motorola modem. I have tried both wireless and with an RJ45 cable and it doesn't make a difference.

My parents have an older Toshiba laptop which connects no problem.
All together we have 3 PC's connected to this network without any issues, but when I try to add the Lenovo to the mix, the connection just craps out.

Any tips?
Thanks