I've got a PC connected to the Ethernet/LAN and a Smart TV to the same Ethernet/LAN.
Is it possible to do mirror casting or video stream over this Ethernet connection instead of WiFi (WiDi)? Ethernet is more stable and faster and would reduce latency and enable FHD streaming, I'd think.
If it's an Android TV, then it has the Google Cast aka "Chromecast Built-in" functionality that lets you cast to your TV from your PC over the network. Whether or not this network connection is via wifi or ethernet does not matter to either device.