Question: how to connect external monitor to compaq laptop?
Answer: Locate the "VGA" port on the side of the Compaq notebook. ... 
Insert the VGA cable into the port and screw down the pins on either side of the cable end.
Run the other end of the cable to the "VGA" port on the input panel of the external monitor.
Press the "F5," "F7" or "F8" key to enable the external monitor function.