What I want to do is connect all the desktops to the modem directly (ethernet cables) and all the laptops/tablets/smartphones to the router through wireless. Because the modem got 1gigabit connection and my router, only supports up to 100mbit. So makes sense to connect all the most heavy used devices to the faster connection and leave the rest for the wifi.
But the problem I have is that when I connect the router directly to the modem, it doesn't get any internet connection (while the desktops do). Only gets successful internet connection if I'm connecting only the router to the modem, without the desktops. Which leaves me with a 100mbit connection for the desktops because I not have to connect them to the router; something I don't want.
How can I bypass that problem and connect all the desktops, including the router to the modem and all to have an internet connection?
And by the way: The router (WHR-300HP) got the latest dd-wrt firmware installed on it.