cable firmly against the motherboard
First things first, make sure your HDMI/DP cable is firmly against the PC motherboard
Because sometimes, your PC case will block your HDMI/DP cable connection
Win+P extended Screen
make sure you have enabled extended screen by pressing Win+P
your display setting should look similar like this, in this example number 4 screen is QCDU
screen on/off button
QCDU screen power on/off button is located on the back side of QCDU, the red button controls LCD screen on and off
