Video Port Specifications

Last Update: November 11th, 2020
Article ID: 381069

Video Port Specifications

While some video port standards have different physical appearances, in some cases video standards are improved through changes to how devices make use of existing connectors and/or by changing how wires inside of cables are designed. Different video standards will also have various limitations with regards to display resolutions, refresh rates, and audio types that are supported.


VGA connections, also known as D-SUB connections, are one of the oldest PC video standards still included on modern displays and devices. Video information is sent to displays using analog signals with no audio channel. Generally the maximum resolution over VGA connections is 1920x1200.


DVI connections are somewhat unique in that they are capable of both digital and analog signals. There are various physical DVI connector pinouts which determine whether digital or analog signals are supported, as well as the maximum resolutions supported.

While a variant does exist for USB data to be carried over DVI alongside a video signal called DVI M1-DA, this is uncommon and not available on Plugable products. Typically DVI will only carry video signals.


HDMI connections have gone through many revisions but the plug itself has remained the same.

As each specification increases the amount of digital data that can be transferred over HDMI cables, the quality of cables has become increasingly important for higher resolutions and refresh rates.

HDMI and DisplayPort also have special considerations for luminance and gamma (HDR) and chroma subsampling data beyond the typical 0-255 RGB values used in DVI and VGA.


Designed as a successor to DVI and VGA, DisplayPort has undergone specification changes similar to those of the HDMI standard. Revisions of this standard have gradually increased the resolution and refresh rate that can be communicated between a PC and display.