VGA, DisplayPort, HDMI, DVI – differences between the interfaces

15.12.2017

There are numerous ways in which graphic content can find its way from the mini PC to the display screen. Graphics cards offer a wide range of connection options (outputs), which in turn have different inputs on the corresponding screens. This often results in a mess, caused by different connection cables behind the monitors. Here we explain in more detail which different connections are available for transferring graphic content, what distinguishes them, what makes them different and which standards they are based on.

An old hand: The analog VGA connection

If we were talking about Indian tribes today, the VGA connection would definitely be the oldest. Because it has been around since 1987. Even if it is slowly dying out, it is still widespread.

VGA stands for Video Graphics Array and is a purely analog interface in which analog signals must first be converted into digital signals. Although this interface was the undisputed standard for around 20 years, it has some disadvantages. The connection was originally designed for a maximum resolution of 640x480 pixels. Nowadays, however, Full HD images can also be output using modern computing methods. However, cables that are too long as well as strong sources of interference can significantly impair the quality of the image, which is why the VGA connection has been replaced by technically more complex interfaces over the years.

Advantage of VGA:

Widespread connection

Disadvantages of VGA:

Only a maximum resolution of 1920 x 1200 possible
Only analog, no digital signal transmission
Reacts sensitively to disruptive factors such as long cables
Only image transmission possible

Digital for the first time: The DVI connection

The successor to the VGA interface is the "Digital Video Interface" - or DVI for short. With the DVI interface, it is possible for the first time to exchange higher resolutions purely digitally. This is achieved by using the so-called TMDS ("Transition-Minimized Differential Signaling") standard, which eliminates the electromagnetic interference common in analogue signals. Although the name of this interface does not suggest it, a so-called DVI-A connector can still be used to transmit purely analog signals if desired. If the standard - a DVI-D connector - is used, the signal is digital and content can be displayed with a resolution of up to 2560x1600 pixels and a frame rate of 100 Hz. The combination of digital and analog signals is also possible with this interface: all you need is a DVI-I connector, where the number of pins increases but the resolution remains the same as that of the DVI-D connector.

Advantages of DVI:

Digital image transmission
Compatible with VGA and HDMI

Disadvantages of DVI:

From today's perspective: "Only" transferable up to two times 1920 x 1200
As with VGA: only image transmission possible

HDMI - Digital sound and image material up to 4K and 3D

The HDMI interface is the direct further development of the DVI interface and is probably the best-known candidate in our round-up today. HDMI, which stands for "High Definition Multimedia Interface", has established itself particularly in the console and home cinema sector.

Using a single HDMI cable, digital sound can be exchanged between two devices in parallel with digital video signals. The HDMI 2.0 standard now also transmits 2160 signals at 60Hz for 4K UHD material and also supports a 1080p resolution of 48Hz for 3D material (see also"What is the difference between Full HD, UHD and 4K?"). The latest version of the HDMI interface has three different connector variants, of which HDMI type A is the standard connector. Type C, the so-called mini-HDMI, is suitable for applications where space is particularly limited. For ultra-mobile applications, the Type D Micro-HDMI is ideal, as it takes up very little space.

Advantages of HDMI:

"2 in 1": Both sound and image transmission possible.
Space-saving
Built-in copy protection (HDCP)
Easy to plug in and unplug

Disadvantage of HDMI:

Not quite as durable as DVI due to its nature

The better HDMI connection? - The DisplayPort

The DisplayPort interface is a license-free connection standard which, just like HDMI, can transmit image and sound signals symmetrically. This was standardized by the VESA (Video Electronics Standards Association) and is intended to make the VGA and DVI connections completely superfluous. Just like DVI and HDMI, DisplayPort is also a digital interface, but is more commonly used in modern computer monitors and graphics cards. The DisplayPort data transmission method is even better protected against interference, which enables a maximum resolution of 5K, i.e. 5120x2880 pixels at a refresh rate of 60 full frames per second.