Before you do anything else, make sure you plug your PC into the right HDMI port. Some TVs only support 4K at 60Hz on certain inputs, so check your TV's manual or the input labels on the back, and ...
Kensington supplied a 4K/8K HDMI to USB-C cable for use with this ... Unfortunately, my own test bed is set up for Thunderbolt 4 devices. I have a single display capable of 4K144 output, but ...