Question When I set FreeSync to "Ultimate Engine", the MAX refresh rate increases from 60Hz to 70Hz ?

[knowledge2121]

I own a Samsung monitor that has freesync, I cannot use the FreeSync feature because my GPU is Nvidia and the HDMI port on the Monitor is 1.4. The monitor's advertised refresh rate is 60Hz.

When I turn FreeSync off using the button on the back of the monitor, the MAX refresh rate I can set in Windows 10 or Nvidia Control panel is 60Hz.

But when I set the FreeSync to "Ultimate Engine", the MAX refresh rate increases to 70Hz.

Why is this ?

Are there any downsides to turning on the FreeSync even If I cant use it ? Should I keep FreeSync off or turn it on ?

 

[Fix_that_Glitch]

What monitor is it?

 

[knowledge2121]

Samsung 27" 60Hz 4ms PLS LED Monitor (LS27F350FHNXZA)