If it's HDMI 1.4 then it doesn't have the bandwidth for more than 30Hz at 4K.
https://en.wikipedia.org/wiki/HDMI#Version_1.4
HDMI 2.0 and 2.1 have much higher bandwidth. 2.1 can do 10K at 120Hz.
@Greenbank started
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If it's HDMI 1.4 then it doesn't have the bandwidth for more than 30Hz at 4K.
https://en.wikipedia.org/wiki/HDMI#Version_1.4
HDMI 2.0 and 2.1 have much higher bandwidth. 2.1 can do 10K at 120Hz.