I've been stuck with this problem for the past couple of months now. I have a Razer Blade 15 that I purchased in January. It has an RTX 2060 in it and I just purchased this HDMI cable, which supports HDMI 2.0b. I then go to the Nvidia control panel and it does not show up with a 240hz refresh rate. The highest refresh rate shown is 60hz. I do not know what is bottlenecking the monitors full potential. Any ideas on how to fix this issue?