Have you checked in the NVIDIA Control Panel, underneath Change Resolution that the refresh rate is correct? Also, there is another setting underl 3D settings that can limit your refresh rate. Ensure that is set to 142Hz ( this sets the maximum refresh rate of the card and NVIDIA recommend it is set to two below your max refresh of your monitor ). Check also the Freesync and G-Sync configuration and especially what they are applied to (Fullscreen or Window and Fullscreen), if you have an adaptive sync monitor.