You should limit output to one HDMI using :0= syntax. All versions support 4K even pi3
I tested it again this afternoon and it turned out to be wrong. The real output resolution is 1920 * 1080. I start 4K output enable, restart the printer, through the screen to observe. The boot interface is normal, but after boot, I click the screen calibration. In 1920 * 1080 LCD screen normal display, when I change to 3840 * 2160 LCD can not display any information.
]]>After I changed to raspberry pi 4B 1.2, it can support 4K. When I upgraded it, I found that it doesn't support 4K. Have you ever met this problem? Is it the system?
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