Help Please!!!

Hello all. i am having a small problem i hope you all can help me with. i bought a ibook laptop, and when i first brought it home, i hooked it right up to my router and it worked no problem. since then my cable modem broke and i bought a new one. and now all my PC's work fine, but for some reason when i plug in my mac, it will not connect to the internet. i have only had it like a month or two, and have no idea how to fix this problem. any help would be greatly apreaciated. thanks in advance.

Go to System Preferences -> Network

Go to your Ethernet adapter

Make sure it is configuring IPv4 using DHCP
Renew your DHCP Lease

Thanks alot but that is not working, still when i open safari all i get it a message saying Safari can't find the server this is driving me mad

One thing, The router you are using, are you sure you plugged the network cable into the right spot?

Also, try unplugging the cable from the back of the PC and into your notebook and see if you get a connection. The way I always check for an internet connection with Broadband is to open up Networking as suggested and see if you have a DHCP ip address.

Have you tried rebooting the laptop? Sometimes when I reboot my wireless network, I need to reboot my iBook too.