N600 Cannot Connect To Internet Or Dial Into Router

I have cable broadband internet.My internet modem is a Ubee D3.0.It is connected to my Netgear N600 Wifi router which have my computer and DirecTV hooked up to it via Ethernet.My wifi went down the other day.Devices were connected, but were not getting any internet service.In troubleshooting, I attempted to dial in to the router using url... as well as 192.168.0.1, and I could not get into the router.I assumed the router must have crashed, and I only purchased it a month ago, so I took it back to the store and exchanged it for a new one.I got home and plugged it in, still not working.I can't access it using the above mentioned methods, and the setup software does not detect a router present.I unplugged the router and hooked the computer up directly to the internet modem.Still no luck.The computer does show a network connection in the system tray, but with no internet.I plugged my laptop in to the internet modem, and I am able to get internet just fine from my laptop. even did a system restore to a restore point last week when I know the internet was working..