Yup, you need a router capable of sending at that speed. You can probably configure your existing gateway to act as a modem only and disable the wifi on it, then plug your router of choice into it. That might be the most cost effective solution, unless your ISP can send you a gateway or modem/router combo that supports those speeds. Working for an ISP myself, I would personally always choose to use my own router instead of the ISP's gateway.