Question Why must I turn on my monitor first before I turn on computer to see graphics?

[gordonmousedeer]

I built a computer for my father recently. This computer has an AMD Ryzen 3 2200G and 8 GB of DDR4 RAM (on an ASRock A320M-HDV R4.0 motherboard). I had difficulty making it show anything on my Acer KG241Q monitor (144 Hz refresh rate, 1 ms response time, 23.6" screen). I found out a way to make this computer show graphics on screen. I must turn on the monitor first then wait until the "Acer" name disappears. When the "Acer" name goes away, I must quickly turn on the computer. Then everything will be normal and the computer will boot Windows 10 properly. This problem sometimes happens to my father's old Samsung SyncMaster 740N monitor. The Samsung monitor connects to the computer through a VGA cable. My Acer monitor connects to the computer through a HDMI cable. May I know why do such display problems happen?

 

[RememberThe5th]

Maybe youre using knockoff cable cause some do not have some pins and that might lead to it.