What is DisplayPort?

Digital data transfer has been further developed: The DisplayPort is a standard for many Mini-PCs and monitors and ensures a resolution of up to 8K @ 60 Hz. What stands behind this digital multimedia interface and what benefits it has, will be explained in this article.

The DisplayPort was standardized by the Video Electronics Standards Association (or for short: VESA). The interface is a licence-free standard for the digital transmission of digital image and sound signals. The specification includes the transmission technique and the appropriate connectors and cables, as well as a guide line for adapters to HDMI and DVI. The reason for the development of DisplayPort was to create a digital interface for higher resolutions and like this, replace the predecessors VGA and DVI. 

Applications of DisplayPort

Since the DisplayPort takes up a lot less space than VGA and DVI, it is perfect for the use in notebooks and also our Mini-PCs. In contrast to the HDMI port, which is mostly used in TV or multimedia devices, the DisplayPort finds its place in the information technology, such as PCs, tablets or monitors.

Data transmission and pin layout of DisplayPort

DisplayPort works pretty similar to PCIe: It is a serial, scalable point-to-point-connection that can adapt the features of the transmission channel. When connecting a graphics card with a monitor, they synchronize and adjust the signal level between 200 and 600 mV.  

DisplayPort has 4 channels available, however, an image signal can be transmitted on only one channel, because each pixel is transferred one after another. DisplayPort also has an additional AUX channel, which on one hand holds the Display Data Channel (DDC) for the transfer of display data, and on the other hand a band width of almost 100 Mbit/s, with which webcams or microphones can be supplied, too.  

Both cable ends of the DisplayPort have the same plug. Like this, each end fits into the graphics card, as well as into the display. A list of the pin layout can be seen here.

Advantages of DisplayPort: Up to 8K resolution

In terms of image resolution DisplayPort has a lot more to offer than its predecessors VGA and DVI, because they only provide 1K respectively 2K resolution. Depending on the version of the DisplayPort a resolution of up to 1K (DisplayPort 1.1), 4K (DisplayPort 1.2), 5K (DisplayPort 1.3) and with the latest specification DisplayPort 1.4 even 8K is possible.

But the interface has some more benefits: First, as already mentioned, DisplayPort is a license free standard. Like this, manufacturers of small series don’t have to pay charges. DisplayPort also has a smaller connector that is not screwable but has a mechanical lock. This safes space and the interface can also be used on small devices.

The progression to DisplayPort 1.4

  • DP 1.1 (2007): The first final version has a maximum transfer rate of 8.64 Gb /s, which is sufficient for HDTV and bigger displays. DP 1.1 is copy-protected with HDCP 1.3 and introduces the feature DP++.
  • DP 1.2 (2009): The most significant change is the increase of the maximum data rate to 17.28 Gb/s. Another innovation is the support of MST (Multi Stream Transport), with which many monitors can be connected using one connector via the Daisy Chain concept.
  • DP 1.3 (2014): The data rate was increased again and now amounts to 25.92 GB/s. Thanks to MST, several 4K UHD- or WQXGA-displays can be connected.
  • DP 1.4 (2016): This version doesn’t contain an augmentation of the data rate, but the introduction and updates of some features: Display Stream Compression 1.2, with which the viewer should not recognize visual differences between compressed and not compressed images, the forward error correction, that reduces transmission errors, and the extension of the audio channels to 32.

Next to the normal developments from DisplayPort 1.1 to 1.4, over the years three special DisplayPorts were developed: Mini DisplayPort, MyDisplayPort and eDP. More information about those can be found here. 

Please enter these characters in the following text field.

The fields marked with * are required.

More on this topic

7 Oct 2019 Array ( [id] => 461 [title] => What is VGA? [authorId] => [active] => 1 [shortDescription] => There are several ways on how to transmit content from a Mini-PC to a display. Today we want to talk about the probably oldest multimedia interface: VGA. [description] =>

In 1987 the company IBM released the computer graphics standard Video Graphics Array (VGA). It specifies a certain combination of screen resolution, color depth and image refresh rate. At the same time also the VGA port, which has its name from the computer graphics standard, was launched as the successor of EGA.

The VGA port

Next to the specification for a physical interface, the VGA port also includes the classification for appropriate cables and plugs.

The VGA plug is a 15 pin Mini-Sub-D-plug with three terminal rows. What these 15 pins are for is shown in this list.

The output at the graphics card is always a socket, the input at the display can be a socket as well as a plug, anyhow the ends are always screwable. Since most of the times a socket is used, the connecting cable has to have a plug on each side. As an alternative there are also cables with a BNC plug on the display side. These have less attenuation and are shielded better than the standard VGA cable, but therefore are more expensive.

Transmission technique of VGA

VGA transmits the data with analogue signals on 5 wires, of which three are responsible to transfer the primary colors and two for the vertical respectively horizontal synchronization. Since the signals are transferred analogously between the graphics card and the monitor, they have to be converted so that the monitor can recognize and display them.

Applications of VGA

Up until the end of the 20th century the consumer electronics and IT were strictly divided. But since the performance of devices in the consumer electronics increased immensely, the borders disappeared. The horizontal frequency of so-called “100 Hz TVs” (31.25 Hz) were very similar to the one in VGA monitors. Thus, tube TVs with VGA port were developed, but at first they were only able to display the standard resolutions of 640 x 400 and 640 x 480 pixels. Many manufacturers in the consumer electronics also use the VGA interface to implement firmware updates for TV devices.
Modern displays are nowadays dependent on digital signals, so at least in need of DVI. By using an adapter the analogue signals can the converted into digital signals, but the image quality decreases a lot by doing so. For that reason the VGA interface is almost completely dead by now.

VGA and 4K – does that work?

The VGA port was initially created for a maximum resolution of 640 x 480 pixels. By using very performant graphics cards and displays, a resolution up to Full-HD, so 1920 x 1080 pixels, is possible. To display content in 4K resolution the VGA port is not enough because its transfer rate is simply too low.

[views] => 5 [displayDate] => DateTime Object ( [date] => 2019-10-07 09:00:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [categoryId] => 234 [template] => [metaKeyWords] => [metaDescription] => [metaTitle] => [tags] => Array ( ) [author] => [assignedArticles] => Array ( ) [media] => Array ( [0] => Array ( [id] => 4563 [blogId] => 461 [mediaId] => 50132 [preview] => 1 [media] => Array ( [id] => 50132 [albumId] => 20 [name] => VGA-Website-Twitter [description] => [path] => media/image/VGA-Website-Twitter.png [type] => IMAGE [extension] => png [userId] => 56 [created] => DateTime Object ( [date] => 2019-11-06 00:00:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [fileSize] => 1541834 [width] => 1420 [height] => 947 ) ) [1] => Array ( [id] => 4564 [blogId] => 461 [mediaId] => 50133 [preview] => [media] => Array ( [id] => 50133 [albumId] => 20 [name] => VGA2-Website [description] => [path] => media/image/VGA2-Website.png [type] => IMAGE [extension] => png [userId] => 56 [created] => DateTime Object ( [date] => 2019-11-06 00:00:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [fileSize] => 835596 [width] => 1085 [height] => 723 ) ) ) [attribute] => Array ( [id] => 458 [blogId] => 461 [attribute1] => NULL [attribute2] => [attribute3] => [attribute4] => [attribute5] => [attribute6] => [digi1Inactivateblogarticle] => 0 [digi1Sponsoredpost] => 0 [digi1Featuredpost] => 0 [digi1Hideblogdetailsite] => 0 [digi1Showleftsidebarblogdetailsite] => 0 [digi1Disablecommentfunction] => 0 [digi1Hideimageslider] => 0 [digi1Relatedblogarticle1] => 465 [digi1Relatedblogarticle2] => 467 [digi1Relatedblogarticle3] => 490 [digi1Relatedblogarticle4] => [digi1Relatedblogarticle5] => [isReference] => 0 [relatedItem] => ) [comments] => Array ( ) ) 1
know-how
What is VGA?
There are several ways on how to transmit content from a Mini-PC to a display. Today we want to talk about the probably oldest multimedia interface: VGA.
21 Oct 2019 Array ( [id] => 465 [title] => What is DVI? [authorId] => [active] => 1 [shortDescription] => The end of analogue image transmission: With the release of DVI data could finally be transferred digitally. What the benefits of DVI are and what else there is to know about, you can read in this article. [description] =>

DVI – The Digital Video Interface

The Digital Display Working Group, which was composed of the companies Intel, Fujitsu and IBM – among others – was responsible for the publication of the DVI port in 1999. The acronym DVI stands for Digital Video Interface and was the first common standard that could transfer images digitally between graphics card and display. Before this, there only was the analogue interface VGA.

Advantages of DVI

As mentioned in the previous paragraph, DVI digitally transfers images. Therefore, the process of converting images from analogue to digital, which was usual for VGA, was no longer necessary. Like this, the images can be directly and without a loss of quality transferred between graphics card and monitor.

Data transfer of DVI

For the digital data transfer DVI uses the standard TMDS. It converts the three color channels into just one serial signal that is occupied with three channels. Since the clock speed is limited to 165 MHz, the maximum resolution is 1600 x 1200 pixels. For higher resolutions up to 2560 x 1600 with 60 Hz the dual link procedure is used. By doing so, an appropriate dual link cable with more pins is used, the video data is spread on to two TMDS transmitters and the clock rate increases to 330 MHz.

Just as usual, also DVI has a maximum cable length. This depends on one hand on the damping ratio and the crosstalk of the connecting cable and on the other hand on the quality of the signal amplification. A cable length of maximum 10 meters can still provide good results, if the cable is longer than that, a DVI amplifier should be used.

Types of DVI

In contrast to VGA DVI has not only one specific pin assignment. Depending on how the pins are assigned, it can be a different type of DVI. The DVI port is divided into two parts: The analogue part on the left with up to 5 pins, and the digital part on the right with up to 24 pins. Furthermore, the DVI cables are screwable, which prevents the cable from falling out of the plug.

The different realizations of the port are shown in this picture. These are:

  • DVI-A: This connector only transmits analogue signals and has 12 + 5 pins. It is usually only used as an adapter cable to VGA.
  • DVI-D: DVI-D cables only transmit digital signals. They either have 18 + 1 contacts (single link) for a resolution of 1920 x 1200 pixels or 24 + 1 contacts (dual link) for a resolution of 2560 x 1600 @ 60 Hz respectively 1920 x 1080 @ 144 Hz.
  • DVI-I: This transmits analogue as well as digital signals. A single link cable has 18 + 5 contacts and reaches 1920 x 1200 pixels @ 60 Hz. A dual link cable has 24 + 5 contacts and a resolution of maximum 2560 x 1600 pixels.

4K with DVI?

As already mentioned before, with DVI the maximum resolution is 2560 x 1600 pixels with 60 Hz. For higher resolutions such as 4K the successor DisplayPort has to be used.

[views] => 3 [displayDate] => DateTime Object ( [date] => 2019-10-21 11:15:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [categoryId] => 234 [template] => [metaKeyWords] => [metaDescription] => [metaTitle] => [tags] => Array ( ) [author] => [assignedArticles] => Array ( ) [media] => Array ( [0] => Array ( [id] => 3174 [blogId] => 465 [mediaId] => 50138 [preview] => 1 [media] => Array ( [id] => 50138 [albumId] => 20 [name] => DVI-Website-Twitter [description] => [path] => media/image/DVI-Website-Twitter.png [type] => IMAGE [extension] => png [userId] => 56 [created] => DateTime Object ( [date] => 2019-11-06 00:00:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [fileSize] => 1275049 [width] => 1334 [height] => 889 ) ) [1] => Array ( [id] => 3175 [blogId] => 465 [mediaId] => 50137 [preview] => [media] => Array ( [id] => 50137 [albumId] => 20 [name] => DVI-2-Website [description] => [path] => media/image/DVI-2-Website.png [type] => IMAGE [extension] => png [userId] => 56 [created] => DateTime Object ( [date] => 2019-11-06 00:00:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [fileSize] => 1529540 [width] => 1326 [height] => 884 ) ) ) [attribute] => Array ( [id] => 462 [blogId] => 465 [attribute1] => NULL [attribute2] => [attribute3] => [attribute4] => [attribute5] => [attribute6] => [digi1Inactivateblogarticle] => 0 [digi1Sponsoredpost] => 0 [digi1Featuredpost] => 0 [digi1Hideblogdetailsite] => 0 [digi1Showleftsidebarblogdetailsite] => 0 [digi1Disablecommentfunction] => 0 [digi1Hideimageslider] => 0 [digi1Relatedblogarticle1] => 490 [digi1Relatedblogarticle2] => 461 [digi1Relatedblogarticle3] => 467 [digi1Relatedblogarticle4] => [digi1Relatedblogarticle5] => [isReference] => 0 [relatedItem] => ) [comments] => Array ( ) ) 1
know-how
What is DVI?
The end of analogue image transmission: With the release of DVI data could finally be transferred digitally. What the benefits of DVI are and what else there is to know about, you can read in this article.
8 Jan 2020 Array ( [id] => 490 [title] => What is HDMI? [authorId] => [active] => 1 [shortDescription] => Probably the most famous interface in our series about multimedia interfaces answers to the name of HDMI. Its cables connect almost everything in the domestic entertainment system. In this article, we want to explain, what hides behind the interface and its fitting cables. [description] =>

The short term HDMI stands for High Definition Multimedia Interface. As well as DisplayPort, and as the name suggests, it stands for an interface for the digital transmission of high-definition video and audio signals. 

Applications of HDMI

HDMI is mostly used to connect devices in the consumer field and for domestic electronics, for instance to connect DVD players, laptops or computers with TVs or monitors.

Which versions does HDMI have?

To keep pace with the constantly progressing technology, HDMI was developed further and further. The different specifications, which by now sum up to 13 in total, confused a lot of customers over years. We also want to keep it short, that’s why we only want to mention the most important updated of the interface:

  • The first HDMI standard 1.0 was released in 2002 and provides a data rate of 4.95 Gigabit/s and a maximum resolutions of 1920 x 1080 pixels.  
  • By introducing the version 1.3 in 2006 the resolution increased to 1560 x 1440 pixels. Furthermore, with this specification a new type of plug was released: HDMI type C.
  • The next major update was version 1.4 in 2009, with an increase of the resolution to 3840 x 2160, i.e. 4K, pixels.
  • The latest version is HDMI 2.1, which was released in 2017 and has a resolution of 7680 × 4320p @ 60 Hz, i.e. 8K.

What do the names for HDMI cables mean?

To ensure a clear and understandable labeling of the cables, they are no longer labeled with the version number (1.0, 1.4, etc.), but with the names for their speed class:

  • HDMI Standard: The data rate of up to 2.25 Gbit/s ensures an image resolution of 720p or 1080i @ 60 Hz. It supports the versions up to 1.3.
  • HDMI High Speed: Resolution of 2160p @ 30 Hz. Supports all versions up to 1.4.
  • HDMI Premium High Speed: Resolution of 4096p @ 60 Hz. Supports versions up to 2.0.
  • HDMI Ultra High Speed: Resolution up to 8K@60Hz. Supports all versions up to 2.1.

Benefits of HDMI

By using HDMI, image and audio can be transmitted with only one cable, which really simplifies the connection of AV devices. Furthermore, like that, another connector is redundant, which helps especially small devices such as our Mini-PCs. In addition, HDMI provides a phenomenal quality, transfers 4K and 3D content and supports Surround-Sound.

[views] => 7 [displayDate] => DateTime Object ( [date] => 2020-01-08 09:30:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [categoryId] => 234 [template] => [metaKeyWords] => [metaDescription] => [metaTitle] => [tags] => Array ( ) [author] => [assignedArticles] => Array ( ) [media] => Array ( [0] => Array ( [id] => 3190 [blogId] => 490 [mediaId] => 50131 [preview] => 1 [media] => Array ( [id] => 50131 [albumId] => 20 [name] => HDMI [description] => [path] => media/image/HDMI.jpg [type] => IMAGE [extension] => jpg [userId] => 56 [created] => DateTime Object ( [date] => 2019-11-06 00:00:00.000000 [timezone_type] => 3 [timezone] => Europe/Berlin ) [fileSize] => 1796976 [width] => 3000 [height] => 2000 ) ) ) [attribute] => Array ( [id] => 487 [blogId] => 490 [attribute1] => NULL [attribute2] => [attribute3] => [attribute4] => [attribute5] => [attribute6] => [digi1Inactivateblogarticle] => 0 [digi1Sponsoredpost] => 0 [digi1Featuredpost] => 0 [digi1Hideblogdetailsite] => 0 [digi1Showleftsidebarblogdetailsite] => 0 [digi1Disablecommentfunction] => 0 [digi1Hideimageslider] => 0 [digi1Relatedblogarticle1] => 461 [digi1Relatedblogarticle2] => 465 [digi1Relatedblogarticle3] => 467 [digi1Relatedblogarticle4] => [digi1Relatedblogarticle5] => [isReference] => 0 [relatedItem] => ) [comments] => Array ( ) ) 1
know-how
What is HDMI?
Probably the most famous interface in our series about multimedia interfaces answers to the name of HDMI. Its cables connect almost everything in the domestic entertainment system. In this article, we want to explain, what hides behind the interface and its fitting cables.