I have one of those modem-router in one devices. Anyway, it only does 2.4ghz or 5, not both at the same time. Everything in my house supports 5Ghz except one device. What is the cheapest way to get my 2.4ghz device connected to my 5ghz router? I figured maybe I could just buy some really cheap 2.4 ghz router and connect it via Ethernet to my main modem.