Comcast says my old modem (surfboard 5101) has reached end of life and is no longer supported. I was forced to get a new modem. I now have the Motorolla SB6183 and cannot get the D-Link DIR-655 wifi router to work with it. I really don't know everything about setting it up, and everything I try...

I am having an issue, right now I have 1 modem (issued from comcast), connected to a wireless router for 4 PCs (2 desk tops and 2 laptops both wireless) my 2 desk tops are wired, one upstairs one down. I also have my PS3 and micro cell tower plugged into the router. The computer upstairs is...