LG 27MQ400 Owner's Manual page 23

HDMI Timing (Video)
Factory support mode
Horizontal Frequency(kHz)
(Preset Mode)
480P 31.50
576P 31.25
720P 37.50
720P 45.00
1080P 56.25
1080P 67.50
Vertical Frequency(Hz)
60
50
50
60
50
60
Recommend Mode
HDMI
O
O
O
O
O
O
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