Good to know: What is VGA?

In 1987, IBM introduced the computer graphics standard Video Graphics Array (VGA). This defines a specific combination of screen resolution, color depth and refresh rate. At the same time, the VGA connection, which owes its name to the computer graphics standard, was launched on the market as the successor to the EGA connection.

The VGA connection

In addition to the specification of a physical interface, the VGA connection also includes the associated connectors and cables.

The VGA connector is a 15-pin mini-sub-D connector with three rows of connections. This list shows the function of these 15 poles.

At the output of the graphics card, VGA is always realized by a socket, the input on the screen can be either a socket or a plug, but is always screwable in any case. However, as a socket is generally used, a connecting cable with two plugs must be used. Alternatively, there are also cables that have a BNC connector on the screen side. These have less attenuation and are better shielded than standard VGA cables, but are therefore also more expensive.

Transmission technology from VGA

With VGA, transmission takes place via analogue signals on 5 lines, three of which are responsible for transmitting the basic colors (RGB) and two for vertical and horizontal synchronization respectively. As the signals are transmitted analogue between the graphics card and the monitor, they must first be converted before the monitor can recognize and display them.

Applications of VGA

Until the end of the 20th century, consumer electronics and IT were kept separate. However, the performance of consumer electronic devices then increased immensely, and so the limits disappeared. The so-called "100 Hz televisions" have a line frequency of 31.25 Hz, which is very close to that of VGA monitors. As a result, CRT TV sets with a VGA connection were created, but these could only display the standard resolutions of 640 x 400 and 640 x 480 pixels. Many consumer electronics manufacturers also use the VGA connector to carry out firmware updates on TV sets.

Modern screens now rely on a digital signal, i.e. at least DVI. Although an adapter can be used to convert the analog signals into digital signals, the picture quality suffers enormously as a result. For this reason, the VGA interface is almost extinct today.

VGA and 4K - is that possible?

The VGA connection was originally designed for a maximum resolution of 640 x 480 pixels. However, using very good graphics cards and monitors, a resolution of up to Full HD with 1920 x 1080 pixels is not a problem. The VGA connection is no longer sufficient for displaying content in 4K resolution, as its transfer rate is too low.

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