I have a cable modem with wifi integrated in it. My PC and another PC in the house is connected to the modem with 2 ethernet cables, but the wifi signal is very weak in some parts of the house and non existant in others. How do i connect another router to the modem where my second pc is. Do i connect the ethernet comming from the modem to the router and then another ethernet cable from the router to the second pc. Is that correct? Will i have 2 seperate wifis ? Do i need something to configure or just to connect?