A VGA monitor is essentially any monitor that can accommodate the output of analogue Video Graphics Array signals – these display units also possess a VGA connector. A VGA connector is located on an extensive range of video and graphics cards in addition to both new and old computer monitors – some high definition TVs also possess the now-antiquated VGA connector. A full sized DE-15 VGA connector typically consists of 15 pins separated in three rows – however, on smaller scale devices such as notebooks and laptop computers, a mini VGA port is utilised instead. The electrical connector DE-15 or D-sub 15 is a D-shaped metal shield used to connect VGA monitors with video source units such as computers and graphics cards. It has also often been referred to as HD-15 (High Density) in order to further distinguish it from the DE-9 found on VGA monitors and cards – an older electrical connector possessing only two rows of connector pins yet the same small, ‘E’ shell.
VGA monitors are fed numerous analogue component signals through connectors and cables: this includes red, green, and blue colour data, as well as horizontal and vertical sync (RGBHV) video signals. They can also process VESA DDC (VESA Display Data Channel) information. However, one limitation of the VGA interface is that it is not designed to accommodate hotplugging: hotplugging refers to the connection or disconnection of the output device while the host system is in operation and still running. Despite this engineering pitfall, users still hotplug a VGA monitor without typically causing damage to the hardware or adversely impacting the system in any major or significant ways. Yet an issue that still persists relates to the design of the VGA connector pins themselves: a VGA monitor is not sufficiently protected against the signal line surges generated through the process of hotplugging.