How can I stop the Render no more than x frame(s) ahead option from resetting to zero when Vertical Sync is set to Always Off?
This is a known bug with the current NVIDIA control panel. Every time that you enter the ‘More Direct3D’ dialog the value is reset to zero, even though your original value is still displayed. To fix this, you have to set the value every time you enter the ‘More Direct3D’ dialog, even if it seems that the value displayed is correct. Hopefully NVIDIA will fix this bug soon.