No image is displayed when I connect the signal cable. Why?

Suggestion:
Step 1: Please manually choose the correct input source from the monitor's OSD menu.
Step 2: If step 1 doesn’t work, please use another cable and select the correct input source from the monitor's OSD menu again.
Step 3: If the monitor still doesn’t work properly after Step 1 and 2, please use another PC/NB or signal cable and change the OSD input source accordingly. If the monitor can work normally, the symptom of no images most likely arises from your graphics card. Please contact your graphics card service center for further support and help.
Step 4: If the monitor still doesn’t work after all above steps, please contact BenQ service center for further assistance.