I have a 2017 iMac Sierra 10.12.5 and i want to connect it to my big tv using a USB-C to HDMi adapter. the Geek squad guy said just plug it in and it will automatically work. From the display menu box it doesnt show any hdmi options. When i called a person in TVs said that the newer macs can only work with a smart tv. HELP! My old one worked with this tv just fine until the hard drive crashed. I need this for my preschool.