how do i set the refresh to 240?

[Windows 10]

Hi, I know my graphics card and monitor support 240hz, but I can't set it to more than 60. I have tried many tutorials to try and fix this problem and couldn't.I just bought this monitor and it came with a new display port version 1.4 I plugged it into the graphics card, can someone help me fix this is really frustrating.

Continue reading...