Download the monitor driver from BenQ and install them. This should fix this minor issue.
LCD = Liquid Crystal Design
LED = Light Emitting Diode
All monitors that are not plasma are LCD. The LED is the lighting behind the screen allowing you to see the screen picture. The old style was lit with a light bulb and not led's which was a lot less efficient. The two (LCD and LED) are not mutually exclusive so this is a non issue.