[SOLVED] Can I use a custom refresh rate (90hz) on a TV without doing harm?

[_dawn_chorus_]

I've been gaming on a Samsung Q60 2019 with a native refresh rate of 120hz (@1080p/1440p). It never lets me choose 90hz naturally. so
will setting the refresh rate to 90hz in a custom resolution have any I'll effect? What about 100hz or any other non multiple of 30?

 

[TerryLaze]

Going below the maximum has no ill effect,if the monitor can't display it it will just show an out of range message.