Hi, I have a Lenovo T470S laptop with Intel HD 520 graphics. I have a 4k monitor that supports 60hz, I have an HDMI cable that says 'High Speed' on it so assume HDMI 2.0, and all drivers are up to date. However, I can't select anything above 30hz. I can't find anything in the Lenovo specs for the laptop that mentions 60hz, does anyone know if the laptop supports it, or could it be something else?