LG Cloud Device 27CN650N Owner's Manual page 31

Input Timing (Video)
Resolution Horizontal Frequency (kHz)
640 x 480p 31.5
720 x 576p 31.25
1280 x 720p 37.5
1280 x 720p 45
1920 x 1080p 56.25
1920 x 1080p 67.50
Vertical Frequency (Hz)
60
50
50
60
50
60
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