Monitor: Samsung 23.5 lc24f390fhmxuf
Connection: HDMI 2.0
Card: Sapphire Radeon RX460 2GB
When FreeSync is enabled (whether standard or ultimate engine, refer to Samsung), 72Hz option gets enabled.
But when you switch to that, colors are washed out (like using limited RGB).
There is an option to set this in the display (HDMI Black Level) but the option gets disabled/greyed out when it's on 72Hz and locks down to standard, not low (which is bad).
This does NOT happen when you connect it to an nVidia card in any circumstances.