The 120Hz screen is off by default in Galaxy S20, Plus and Ultra for a specific reason. So, when playing games, such as Fortnite, Marvel Tournament of Champions, Mortal Kombat, Vainglory, etc. you can switch to the 120Hz refresh rate for smooth interaction. In Galaxy S20, S20 Plus, and S20 Ultra, the 120 Hz display is off by default. You will need to visit the Motion Smoothness menu under the Display settings to switch between 60Hz and 120Hz.
Switch 60Hz and 120Hz display refresh in Galaxy S20 series phones
FYI, if you set a 120Hz refresh rate in your Galaxy S20, S20 Plus or S20 Ultra for your day-to-day stuff, the battery will drain faster. Also, you can’t use the phone at its Quad HD 1440p resolution. Samsung has limited 120Hz refresh to Full HD 1080p resolution, to reduce the battery drain. So, choose between the clearest or the fastest version of the screen with the above steps.
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