In This Article
What is Digital Visual Interface (DVI)?
Digital Visual Interface or DVI refers to the specific video display interface that transmits video signals to display images at higher resolutions of up to 2560 x 1600 pixels.
It can transmit only video signals and not audio signals. It typically supports connecting digital-to-digital devices only.
KEY TAKEAWAYS
- DVI can carry video signals much faster and its high resolution supports make the images look much more realistic. It is very easy to use and also comes with backward compatibility.
- The technology behind this interface sends uncompressed data in binary form without the need of any specific software or driver.
- There are different types of DVI available such as DVI-A, DVI-D, and DVI-I. The dual link DVI offers double the speed of a single link DVI since it uses two TMDS 165 MHz transmitters instead of one.
- The major specs supported by DVI are maximum data rate of more than 9 GB/s, resolutions of 2560 × 1600 pixels at 60 Hz and 3840 × 2400 pixels at 30 Hz and a refresh rate of up to 144 Hz.
Understanding Digital Visual Interface (DVI)
Basics
Digital Visual Interface, commonly referred to as DVI, signifies a specific standard of video connection.
It is created by DDWG or the Digital Display Working Group and supports both analog and digital video signals.
However, apart from a few specific types of DVI connectors, this standard does not support audio signals.
Therefore, it can be used in computers and other displays but not for TVs.
The DVI connectors can convert the digital video signals into analog video signals and if the signal is already digital there is no need for any conversion before transmission.
There are different types of DVI connectors that may even support high bandwidth signals in excess of 160 MHz.
This means that you can use these connectors with high resolution displays such as HDTV and UXGA.
Depending on their type, the DVI can have a lot of uses.
Design
The Digital Visual Interface is designed to connect different display devices at resolutions as high as 2560 x 1600 pixels to transmit both analog and digital video signals.
It was ideally designed to replace the legacy display systems that used analog video signals.
Though the Digital Visual Interface does not carry audio signals, it is quite compatible with High Definition Multimedia Interface or HDMI.
However, there are a few that are used in the TV and can carry audio-visual data, as said earlier.
However, if the hardware of the device it is connected to does not support such data, an adapter is required to combine the analog and digital audio with the DVI data.
Importance
The importance of the Digital Visual Interface cannot be ignored simply due to the fact that it can transmit both analog as well as digital video signals.
This means that you can use a CRT monitor or an LCD with your computer if it supports DVI.
The analog video signals from your computer will be converted by the DVI to display digital images on the LCD.
And, for the CRT it will not need any conversion since it supports analog video signals.
There are some other features of the DVI that makes it quite important such as:
- It carries signals much faster and better than a VGA port
- The images displayed look much more realistic being of high quality
- Better backward compatibility and
- Simple plug and play usage.
Technology and Working Process
The technology used in the Digital Visual Interface allows it to send uncompressed data over it to specific display devices.
The data that is transmitted is in binary form at all times.
After the data is transferred, the pixel received from the source is reflected exactly in the same way as it is received on the display unit.
This is where the DVI technology differs from the analog systems which are known to have both electric and noise attenuation which degrades the quality of the final image displayed on the output unit.
Apart from that, the DVI technology also has the capability to trim down overall energy usage.
The best part of the Digital Visual Interface technology is that it does not need any specific type of drivers or software to be downloaded and installed to use it.
However, the device that you want to use it on should support DVI in the first place.
Types of Digital Video Interface
There are different types of DVI ports available and you should use one according to your needs and preference. These are:
DVI-A
Here the letter ‘A’ stands for analog signal and this older version of DVI offers high resolution analog video output.
However, this is not used by many people these days since it can transfer only analog signals to the monitor and not digital signals to it.
It can support a maximum resolution of up to 1920 x 1080 pixels.
A DVI-A can be identified easily with its single bar located at the right corner that comes with 2 pins below it and 2 pins above it.
It also comes with an additional 12 pins with it.
Ideally, DVI-A is the type that you want if you want to connect a VGA monitor to a DVI computer such as a low-cost LCD or a CRT monitor because they both carry the same video signal – analog.
However, expect some loss in the picture quality due to digital to analog conversion.
DVI-D
Here the letter ‘D’ stands for digital and it is used by many users because most of the displays today support digital signals and this interface offers true digital video output.
However, connecting a DVI-A with a DVI-D is not allowed because the former reads analog video signals only and the latter reads digital video signals only.
The cables used here establish a direct contact with the source video or the video cards and the output units.
This ensures a much better and faster data transmission which results in images of much higher quality in comparison to analog video signals.
The digital format also helps in the process since it removes the need for an analog conversion before transmission.
There are two further types of it such as:
- Single Link – This typically comes with two blocks on its sides and a bar. Each of the blocks have 9 pins and support a maximum resolution of up to 1920 x 1080 pixels.
- Dual Link – This also has a bar but there are three rows in it, each of which having 8 pins in them. It can support a maximum resolution of up to 2048 x 1536 pixels.
Out of these two types, the Dual link DVI-D port is more commonly used these days because it can transfer two signals to the monitor, which results in maximum resolution support as opposed to one signal transmitted to the monitor by a Single link port.
DVI-I
You will get the best of both worlds in terms of the performance of this particular port.
The DVI-I ports can transmit both analog and digital video signals and therefore you can connect it to a DVI-A or a DVI-D.
And, just like DVI-D, the DVI-I also comes in two further variants namely, Single Link and Dual Link with the following design aspects:
- The DVI-I Single link comes with a bar that has 2 pins above it and 2 pins below it as well as 2 blocks with 9 pins in each of them. It supports a maximum resolution of up to 1600 x 1200 pixels.
- The DVI-I Dual Link port, on the other hand, also has a bar with 2 pins below and above it but has 3 rows with 8 pins in each of them. This supports a resolution of up to 2048 x 1536 pixels.
Since the DVI-I ports can transfer analog to analog signal or a digital to digital signal, these ports are considered to be more versatile and can be used in almost all environments.
However, all these formats of Digital Visual Interface are not interchangeable.
This means that a DVI-A will not work on a digital system and a DVI-D will not work on an analog system.
However, if you want to connect an analog source to a digital display you will need to use a VGA to DVI-D electronic converter.
On the other hand, in order to connect a digital output with an analog monitor, you will have to use a DVI-D to VGA electronic converter.
Single and Dual Link DVI
These specific types of DVI ports use a specific type of digital information format to send signals.
This is called the Transition Minimized Differential Signaling or TMDS.
The Single link cables typically utilize only one TMDS 165 MHz transmitter but the Dual link cables use two of them.
This means that the Dual link DVI pins will have double the power and speed of transmission which will significantly increase the quality of the signal and eventually that of the picture displayed.
In terms of compatibility, you can use a Dual link cable in place of a Single link cable in most cases but the same cannot be said if you want to go the other way around.
However, be wary about the limiting factor with respect to the number of pins available in the female connector when you want to use a Dual link cable for a Single link application.
It is the same thing as using a DVI-I cable in place of a DVI-D cable.
Length of Cables
According to the official Digital Visual Interface specification mandate, the length of the cables is 5 meters or 16 feet.
However, nothing can be said with certainty because manufacturers do extend that limit depending on the strength of the cards and the size of the monitors.
Therefore, the cable length can be even 25 feet or longer.
It is needless to say that the final results will vary in terms of quality if you use a longer cable without using a powered signal booster along with it.
The quality of the cable as well as the length of it will make the difference in the quality of the image.
For example, for any unstable DVI run, there will be effects such as:
- Artifacts in the images
- Sparkling of the pixels on the display
- Flickering or shaking of the images or even
- A blank display.
In order to avoid such issues you should not go for any cable that is longer than 9 or 10 meters.
DVI Cable to Use
In order to ensure a better display, you will need to make sure that you use the right type of DVI cable as well.
Check the female DVI plugs to figure out the signals they may be compatible with. For example:
- You will need a DVI-D cable if one or both the connections are DVI-D
- You will need a DVI-A cable if one or both the connections are DVI-A
- You will need a DVI/VGA adapter or a DVI to VGA cable if one connection is DVI which supports analog signals and the other is VGA and
- You may use a DVI cable if both connections are DVI-I but using a DVI-I cable in particular is better.
However, if one connection is analog and the other is digital, you cannot connect them with one single cable in any way.
For that, as said earlier, you will need to use an analog VGA to digital DVI/HDMI converter electronic box.
Identifying a DVI Cable
You will need to identify the right digital or analog cable as well depending on the characteristics of the two variables usually found in each DVI connector such as the flat pin on one side and the pin sets.
Here, the flat pin helps to determine whether the DVI cable is digital or analog. If there is a flat pin with four more pins around it, it signifies that it is either a DVI-A or a DVI-I.
On the other hand, if there is only the flat pin, it is a DVI-D cable.
Similarly, the variance in the pin sets helps in determining whether the cable is Single link, Dual link, or analog.
For example, a Single link cable will have two distinct 9-pin sets and a Dual link cable will have a solid 24-pin set.
However, if there is a separated 8-pin and 4-pin set, it indicates a DVI-A cable.
Functions of Digital Visual Interface
The primary function of the Digital Visual Interface is to carry both digital and analog video signals.
The best part of it is that there is no need to use a separate cable for it because it can be carried through a single cable as such.
There are also some special types of DVI connectors that are designed to carry audio signals.
Is DVI Better than HDMI?
Well, to answer this question you will need to understand a few other aspects of Digital Visual Interface which will help you to make a much better and more accurate comparison between the two and make a final decision yourself.
And, remember, it always depends on personal preference.
Here are the distinguishing factors between the two interfaces:
- The DVI connectors will typically have a much larger footprint in comparison to the HDMI connectors.
- As for the shape of the connectors, these are square and are fixed with two screws to ensure security as opposed to the HDMI connectors that come with a slim rectangular shape and there are no screws to ensure security. .
- When you compare the design of the DVI, you will see that the front of the connector typically comes with 24 primary pins arranged in a 3-row matrix. And there are 4 extra pins to the right side of these pins. In comparison, the HDMI comes with only 19 pins.
- As for the ports, you will find different types of DVI ports which include DVI-A, DVI-D, and a range of DVI-I, as said earlier. However, these ports are not interchangeable.
Some other major specifications of the Digital Visual Interface are:
- It supports a maximum data rate of in excess of 9 GB/s
- It supports resolutions of up to 2560 × 1600 pixels at 60 Hz and 3840 × 2400 pixels at 30Hz which is much more than the need of most of the average users and
- It supports a refresh rate of up to 144 Hz but at a much lower resolution as compared to the HDMI.
In comparison, the HDMI designed by a group of companies such as Hitachi, Philips, Panasonic, Thompson, Silicon Image, and Toshiba in 2002, can transmit both high-quality video and audio signals together.
The DVI, on the other hand, can transmit only video signals, but both analog and digital in nature.
If you are into gaming or do some high-end and graphics intensive tasks on your computer, you will find an HDMI to be far better in comparison to the DVI.
Typically, HDMI is not only considered to be a common standard for gaming, but also for high-end computing and television needs.
There are also mini and micro HDMI ports available that support a wide variety of compact devices such as smartphones and tablets.
Therefore, HDMI surely has much more utility than the DVI.
Some of the noteworthy specifications of the HDMI are:
- It supports a maximum data transfer rate in excess of 42 GB/s
- It supports higher resolution up to 4K at 144 Hz and 8K at 120 Hz
- It provides HDR or High Dynamic Range video output support and
- It also supports 32 audio channels including DTS HD and Dolby True HD.
Are you lamenting that you have a DVI and not an HDMI? Well, there is no need to worry because you can easily convert DVI signals to HDMI by using an adapter.
What Devices Use Digital Visual Interface?
The Digital Visual Interface is commonly used in several digital display units which include and are not limited to:
- Computers
- Projectors and
- LCD or Liquid Crystal Display monitors.
A few specific types of DVIs, especially those that can carry audio signals along with analog and digital video signals are also used in TVs.
Is Digital Visual Interface Still Used?
It is true that the Digital Visual Interface connection has started to fade out but it is still used on the graphics cards.
The video signal and output is almost the same as the HDMI but it does not carry audio signals.
Due to the latest tweaks made in its features that help it to transmit digital data through three communication channels in each connector link, DVI still has a pretty wide use in both domestics as well as in business settings.
Does Digital Visual Interface Carry USB?
Yes, the Digital Visual Interface with 30-pin connectors, which is also referred to as M1 connectors often, can carry both analog and digital video signals as well as data like a USB or Universal Serial Bus.
Is Digital Visual Interface Needed for Computer Monitor?
A Digital Visual Interface is essentially required as a visual standard if you have an older monitor of high quality and want to connect it to your computer.
The best part of the DVI which is developed by the Digital Display Working Group or DDWG is that it supports analog and digital video signals over a single cable.
Can Digital Visual Interface Support 4K?
Typically, there are some specific limitations in terms of resolution supported by the single dual-link DVI ports which have a maximum of up to 2560 x 1600 pixels at 60 Hz. Therefore, a DVI port may not support 4K video output.
If you want to attain a 4K resolution at 60 Hz, you will probably need to use two such dual-link DVI cables.
So, it is better that you use either a DisplayPort 1.2 or an HDMI 2.0 for a higher resolution support.
This is because even the dual link DVI is stuck below 4K while the DP can do much more than 8K at 60 frames per second at 10 bit color with its latest feature and tweaks.
Is Digital Visual Interface Better than VGA?
Well, it depends on the type of the monitor as well as the support offered by the GPU or Graphics Processing Unit.
If these support both VGA and DVI, you are recommended to use a DVI cable instead of a VGA or Video Graphics Array.
This is because with the newer DVI cables, where ‘D’ stands for digital, the quality of the images will be much better than VGA, which supports only analog video signals.
However, a lot of people think that the future of the Digital Visual Interface or DVI is not very bright and will soon join VGA in the oblivion.
People often cite its incompatibility with the future Graphics Card Units as the main reason behind it, where, in fact, a few of the GPUs do not even have a DVI for that matter.
True as it is in parts, the DVI still has got some steam in it and a place in the world of computers.
Most importantly, it is the only interface that comes with the ability to carry both digital as well as analog video signals.
You may rest assured that it will still be used for at least 5 to 6 years down the lane, though 10 seems to be more likely and a reasonable figure.
Yes, it may eventually be replaced by DisplayPort and HDMI or High Definition Multimedia Interface, but it is quite hard to imagine with the kind of performance benefits it offers that it will happen anytime soon, that is in less than 5 years at the minimum.
Therefore, the Digital Visual Interface is still good to go for and, most importantly, the fact that its price is quite fair, you should not really bother about it.
Till the time 4K becomes mainstream, which is actually far away from happening, you should not strike off DVI completely from your list of options.
Conclusion
With all the features and functionalities of the Digital Visual Interface explained clearly for you, you now surely know about its utility as well as its future, since talks of it going to the VGA are already on.
Still, it is quite useful as it is established in this article.