Connector on dvi card. Main differences and similarities between DVI-I and DVI-D

Today you can display a video image on a monitor or TV in different ways– there are more and more port options for connection every year, and it’s not surprising to get confused in the number and difference of interfaces.

Let's look at the most popular formats and determine cases when a particular video port standard fits better everything.

VGA

The oldest standard for pairing a PC and a monitor, which still exists today. The component video interface, developed back in 1987 by IBM, uses analog signal to transmit color information. Unlike more modern standards, VGA does not allow sound transmission - only pictures.

The VGA connector is usually blue with two screws on the sides. It has a 15-pin connector and initially could only work at a resolution of 640 by 480 pixels, using a palette of 16 colors. The standard later evolved into the so-called Super VGA, supporting higher screen extensions and up to 16 million colors. And since the improved standard continued to use the old port and did not change in appearance, it is simply called VGA in the old fashioned way.

More often this format used on older hardware, but many computers still have this port. What is called - just in case.

DVI

More than ten years after the release of the VGA standard, the DVI format, a digital video interface, saw the light of day. Released in 1999, the interface was capable of transmitting video without compression in one of three modes: DVI-I (Integrated) – a combined digital and analog transmission format, DVI-D (Digital) – supporting only digital signal, DVI-A (Analog) – supports only analog signal.

DVI-I and DVI-D ports can be used in single or dual mode. In the second case, the bandwidth is doubled, which allows you to obtain a high-definition screen resolution - up to 2048 by 1536 pixels. However, for this you need to have an appropriate video card. The ports themselves differ in the number of contacts - so Single link mode uses four twisted pair wires (maximum resolution 1920 by 1200 pixels at 60 Hz), and dual mode (Dual link), respectively, larger number contacts and wires (resolution up to 2560 by 1600 at 60 Hz).

It is important to remember that the analog version of DVI-A does not support DVI-D monitors, but a video card with DVI-I can be connected to DVI-D monitor cable with two DVI-D-male connectors. Similar to VGA, this standard also transmits only video images to the screen without sound. However, since 2008, video card manufacturers have made audio transmission possible - for this you need to use a DVI-D - HDMI cable.

You can also find on the market the mini-DVI format, invented by Apple, prone to reducing everything and everyone. However, the mini-standard only works in single mode, which means it does not support resolutions higher than 1920 by 1200 pixels.

HDMI

High Definition Multimedia Interface or high-definition multimedia interface allows you to transmit digital video and audio signals, and even with the possibility of copy protection. HDMI is smaller in size than its predecessors, operates at a higher speed, and most importantly, transmits sound, which made it possible to retire the previous SCART and RCA (“tulips”) standards for connecting video devices to TVs.

The HDMI 1.0 specification appeared at the end of 2002 and had a maximum throughput 4.9 Gb/s, support for 8-channel audio and video up to 165 MPix/sec (that is, FullHD at 60 Hz). Since then, the standard has constantly evolved, and in 2013 the HDMI 2.0 specification was released with a bandwidth of up to 18 Gbps, support for 4K resolution (3840 by 2160 pixels at 60 Hz) and 32-channel audio.

Today, the HDMI standard is used not only by computers, but also digital TVs, DVD and Blu-ray players, game consoles and many other devices. If desired, you can use adapters from HDMI to DVI and vice versa.

The number of pins on HDMI ports starts from 19, and the connectors themselves are available in several form factors, the most common of which are HDMI (Type-A), mini-HDMI (Type-C), micro-HDMI (Type D). In addition, there is HDMI ports for signal reception (HDMI-In) and transmission (HDMI-Out). Outwardly, they are practically indistinguishable, but if, say, your monoblock has both ports, then when you try to display a picture on a second monitor, you can only use one of them, namely the HDMI-Out one.

DisplayPort

In 2006, another video standard for digital monitors was adopted. DisplayPort, like HDMI, transmits not only video, but also audio, and is used to connect a computer with a display or home theater. DisplayPort has more high speed data transfer, support for resolutions up to 8K (7680 by 4320 pixels at 60 Hz) in version 1.4, released in March 2016, and the image through the port can be displayed on several monitors (from two to four, depending on the resolution).

DisplayPort was specifically designed to output images from computers to monitors, while HDMI was more intended for connecting various devices to the TV. However, these ports can be used together using a Dual-Mode DisplayPort adapter.

There are also variations of Mini DisplayPort, used primarily in laptops. In particular, the smaller format is loved by Apple.

Thunderbolt

Finally, the standard from Intel(at working together from Apple) to connect peripheral devices to your computer. It was Apple that was the first to release a device with this interface in 2011 - MacBook laptop Pro.

The maximum data transfer speed is 20 Gbit/s when using optical fiber for version 2, while the 3rd version of the interface is capable of operating at speeds up to 40 Gbit/s. Thunderbolt combines not only DisplayPort interface, but also PCI-Express, which means you can connect almost anything to it. In particular, you can connect up to six devices to one port, which reduces the need to have a huge number of different ports on a device.

The Thunderbolt connector itself is smaller than the mini-DisplayPort, and its third version is a port compatible with USB 3.1, that is, it is made with a USB Type-C connector.

Universal USB

If you are suddenly worried that you will soon have to update all your home appliances due to changing standards, then do not rush. Manufacturers are striving to simplify the story with numerous interfaces and provide support for older devices through adapters. In particular, for HDMI devices you will only need to use an appropriate adapter in order to be able to connect to a modern USB port Type-C.

By analogy with the fact that previously each manufacturer mobile phones had its own charging connector, and now most people use micro USB port, the video standard also strives for unification. And the unifying form factor should be the USB port latest generation, through which both monitors and regular headphones and headsets will be connected.

Among the most common interfaces for connecting monitors to a PC are DVI-I and DVI-D. What are the features of each of them?

Facts about DVI-I

DVI-I interface involves the use of two types of signal transmission channels - analog and digital. Moreover, the structure of their location in the cable may differ depending on one of the two modifications of the interface in question - DVI-I Single Link and DVI-I Dual Link.

In devices type DVI-I Single Link supported 1 digital and 1 analog channels. Moreover, both of them function independently. Activation of any of them is related to which specific device is connected to the PC’s video card and how the connection between devices is made. Devices of the DVI-I Dual Link type, in turn, implement 3 data transmission channels - 2 digital and 1 analog.

Facts about DVI-D

DVI-D interface involves the use of only digital data transmission technologies. Depending on the cable modification, 1 or 2 channels can be used.

Using a single channel interface DVI-D type You can transmit data in a resolution of about 1920 by 1200 pixels and a frequency of 60 Hz. However, these resources will not be enough to display 3D images created using technologies like nVidia 3D on a PC monitor.

The presence of dual-channel DVI-D interfaces in the cable structure allows you to transfer video data to high resolution- 2560 by 1600 pixels. In addition, the presence of two digital channels When using such a cable, it makes it possible to broadcast 3D images on monitors in a resolution of 1920 by 1080 pixels and a frequency of 120 Hz.

Comparison

The main difference between DVI-I and DVI-D is that the first standard supports both digital and analog data transmission technologies, while the second supports only digital ones. Accordingly, when connecting a monitor to a PC via DVI-D, you should check whether it is analog.

Visually, the DVI-D interface - in all modifications - differs from DVI-I in the absence of four holes in the side of the connector.

In fact, both standards under consideration are combined into a DVI-I Dual Link connector. There is also, by the way, the DVI-A interface, which supports only analog data transmission technology.

Having determined what the difference is between DVI-I and DVI-D, we will record the main conclusions in the table.

The standard provides simultaneous transmission of visual and audio information per cable, it is designed for television and cinema, but PC users can also use it to output video data using the HDMI connector.

HDMI is the latest attempt to standardize a universal connection for digital audio and video applications. It immediately received strong support from the giants of the electronics industry (the group of companies developing the standard includes companies such as Sony, Toshiba, Hitachi, Panasonic, Thomson, Philips and Silicon Image), and most modern devices output high resolution has at least one such connector. HDMI allows you to transmit copy-protected audio and video to digital format over one cable, the first version of the standard was based on a bandwidth of 5 Gb/s, and HDMI 1.3 expanded this limit to 10.2 Gb/s.

HDMI 1.3 is the latest standard specification with increased interface bandwidth, increased clock frequency up to 340 MHz, which allows you to connect high-resolution displays that support more colors (formats with color depth up to 48-bit). New version The specification also defines support for new Dolby standards for transmitting compressed audio without loss of quality. In addition, other innovations appeared; specification 1.3 described a new connector, smaller in size compared to the original.

In principle, the presence of an HDMI connector on a video card is completely optional; it can be successfully replaced by an adapter from DVI to HDMI. It is simple and therefore included with most modern video cards. Moreover, on video cards of the HDMI series the connector is in demand primarily on mid-range and lower levels, which are installed in small and quiet barebones used as media centers. Because of the built-in audio, the Radeon HD 2400 and HD 2600 graphics cards have a definite advantage for builders of such multimedia centers.

Based on materials from the company's website iXBT.com

The digital DVI interface replaces the analogue VGA interface used in most older monitors, which has existed unchanged for over a decade. The need for such an “upgrade” has been brewing for a long time: the analogue method of data transmission had many disadvantages, first of all, significant restrictions on the amount of transmitted information, and therefore on the maximum resolution that the monitor can support.

The first versions of DVI were based on a serial data format and used three channels carrying video and additional data streams, with a throughput of up to 3.4 Gbit/s per channel.

At the same time, increasing the cable length had a negative impact on the maximum permissible volume of transmitted data. Thus, a cable 10.5 m long can be used to transmit an image with a resolution of up to 1920 × 1200 pixels, and if its length is increased to 15 meters, then it is unlikely that it will be possible to transmit an image more than 1280 × 1024 pixels without loss of quality (in extreme cases you will have to use several cables and special signal amplifiers). To ensure compatibility, several types of DVI cables have been developed, differing not only in their characteristics, but also in their connectors. By looking at the connector, you can understand what characteristics the cable has - namely, what data it can transmit and in what volume.

The simplest option is DVI-A Single Link. The letter A in this abbreviation means “analog”. Such a cable is not capable of transmitting digital data at all, and, in fact, is an ordinary VGA cable equipped with a DVI connector. You can find such a cable in real life quite difficult.

DVI-I cables support both analog and digital transmission data. This cable is one of the most common: the letter “I” in the abbreviation stands for “integrated”, and means that this cable has two independent data transmission channels - analog and digital. Using such a cable, you can connect both a digital monitor and an analog one (for example, an old CRT monitor). To do this, you will need an inexpensive DVI-VGA adapter.

Finally, DVI-D cables only support digital data transfer. You won't be able to connect an old analog monitor to them. In particular, you need to remember this when choosing a video card: by looking at the connectors available on it, it will become clear which monitors can be connected to it and which cannot.

The DVI-I connector has more pins than the DVI-D connector. Additional contacts at DVI-I connector are responsible for transmitting a signal in an analog format, which is absent from the DVI-D connector.

Finally, we need to talk about the Dual link variation (dual mode), which is found in DVI-I and DVI-D cables. The DVI standard implies the ability to double the channel bandwidth by adding several additional pins to the connector.

Thanks to this, the cable can transmit twice as much information, and therefore the monitor can be set to a higher resolution and refresh rate. Without Dual Link the display technology will also not work three-dimensional images nVidia 3D Vision, for the implementation of which you must have a refresh rate of 120 Hz and a resolution of 1920x1080.

If we take the standard screen refresh rate of 60 Hz, then the Single Link cable will provide a resolution of up to 1920x1080 pixels, and the Dual link will allow you to transmit an image in a resolution of up to 2560x1600 pixels.

The conclusion that can be drawn from these figures is clear: to connect digital monitors with a relatively low resolution by today's standards, any digital DVI cable - Dual link in in this case not required. If the monitor supports resolutions such as 2048x1536, 2560x1080 or 2560x1600 pixels, then dual mode will be indispensable.

If the house has old monitor with an analog VGA connector, but the video card does not have such a connector, you will have to make sure not only that an adapter is available, but also that the cable supports analog data transfer (that is, it is equipped with a DVI-I connector).

Types DVI connectors and their technical characteristics

Many people have the problem of correctly identifying and selecting the necessary adapter for a video card or monitor. To make this task easier, we present to your attention a table of differences indicating the type of DVI connectors, as well as information about their technical characteristics.

Types of DVI

DVI-A is analog transmission only.
DVI-I - analog and digital transmission.
DVI-D is digital transmission only.

Video cards with DVI-A do not support monitors that comply with the DVI-D standard.
A video card with DVI-I can be connected to a DVI-D monitor (with a cable with two DVI-D-male connectors).
A DVI-I to VGA adapter exists.
There is no DVI-D to VGA adapter with video transmission function, only special converters that have a high cost (from 35 USD). There are DVI-VGA technology adapters on sale that serve other purposes and are not suitable for video signal conversion.

Specifications

The data format used in DVI is based on PanelLink, a serial data format developed by Silicon Image. Uses technology high speed transmission TMDS digital streams (Transition Minimized Differential Signaling, differential signal transmission with minimization of level differences) - three channels transmitting video and additional data streams, with a throughput of up to 3.4 Gbit/s per channel.

The maximum cable length is not specified in the DVI specification because it depends on the amount of information being transferred. The 10.5 meter cable can be used to transmit images with a resolution of up to 1920 x 1200 pixels. Using a cable 15 meters long it will be possible to transmit an image in normal quality with a resolution of 1280 x 1024 pixels. To amplify the signal when transmitting over long cables, special devices are used. When using them, the cable length can be increased to 61 meters (in the case of using an amplifier with its own power supply).
Types of DVI connectors

Single link DVI uses four twisted pairs of wires (red, green, blue, and clock) to provide the ability to transmit 24 bits per pixel. With it, the maximum possible resolution of 1920x1200 (60 Hz) or 1920x1080 (75 Hz) can be achieved.

Dual link DVI doubles the bandwidth and allows for screen resolutions of 2560x1600 and 2048x1536. Therefore, for the largest LCD monitors with high resolution, such as 30" models, a video card with dual-link DVI-D Dual-Link output. If the monitor has a maximum screen resolution of 1280x1024, then connecting it with a dual link cable does not make sense, because... this cable Designed for monitors with higher resolution.

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