I have a Dell Inspiron 5559. The WiFi just quit working. It works at 100 mbps when wired to a gigabit ethernet router. I assume this means it is limited by a 10/100 T ethernet capability. I also assume installing a WiFi dongle will restore my connection to the router, but I have a couple of questions: 1. As I don't want to take up anothe USB port,is there such a thing as a WiFi dongle that plugs into the Ethernet jack on the laptop? 2. If I install a dongle (USB or rj45) that supports gigabit speed, will I still be limited to 100 mbps? Any help would be appreciated.