The DVI connector is not the easiest to understand. It is quite popular, but it also has a lot of diversity within it.
“Does DVI transmit digital or analog signals?”
This is a question that many PC and projector users want answers to. Analog systems are phasing out fast, so people want to know what connectors are still relevant.
This article explores the differences in DVI connectors. It also compares the popular transfer interfaces: DVI, VGA, and DisplayPort.
- What is DVI?
- Is DVI Digital or Analog?
- Types of DVI Formats
- What Are Single and Dual Links?
- Differences Between DVI-A, DVI-D, and DVI-I
- DVI Cables
- DVI vs VGA vs DisplayPort
What is DVI?
DVI is a video display interface. In 1999, the Digital Display Working Group (DDWG) designed it to transmit digital video at resolutions up to 2560 × 1600.
You can find this connector on computer monitors, PCs, and projectors. Although less common, it is also present on TVs and DVD players.
DVI is the standard transfer interface for computers, so most computers have at least one DVI port. Although HDMI is the connector of choice for HDTVs, some TV manufacturers still slip in a DVI port.
The DVI connector looks like a larger version of VGA, and its cables support up to a 9.9 Gbps transfer rate.
Is DVI Digital or Analog?
The DVI connector interface is quite complex. It comes in different formats; each is different from the others in appearance and function.
Generally, the DVI interface can transmit both digital and analog signals. However, the capabilities of your specific connector depend on its format.
There are three DVI connector formats, and we’ll discuss them in the next section.
Types of DVI Formats
The DVI connector formats include DVI-I, DVI-D, and DVI-A. These three formats have different functions, which we’ll explain below.
If you’re guessing the A in DVI-A refers to “Analog video,” you’re right! The DVI-A format caters only to high-quality analog videos.
DVI-A allows you to transmit analog signals from a DVI source to an analog display (i.e., a DVI DVD player to a CRT monitor).
You can also use a DVI-A to VGA adapter to connect to VGA display devices. This feature is very convenient; DVI-A and VGA support only analog signals, so there is no signal conversion and quality loss.
The DVI-D format is responsible for only digital video transmission. It is the connector of choice for transmitting digital signals between source devices and LCD monitors or HDTVs.
DVI-D does not convert signals from the source to analog format (unlike VGA). Hence, the connection between the source and display devices remains strong.
The DVI-D interface can transmit digital signals to HDMI and DisplayPort connectors using adapters, but it does not support special features like CEC and HDMI ARC.
The I in DVI-I stands for “Integrated” because this format supports both digital and analog transmissions. It can transmit either analog-to-analog or digital-to-digital signals.
Due to its convenience, DVI-I is the most common DVI port format. You can use it to connect to any display device: digital or analog.
DVI formats are not interchangeable. You cannot use a DVI-D connector to transmit analog signals, and you cannot transmit digital signals over a DVI-A connector.
In both cases, you will need to use converters to convert from your DVI format to a connector on the display device. Check out the DVI-D to VGA adapter for analog displays.
However, if your source device supports the DVI-I format, you may transmit analog or digital signals — depending on your display device.
What Are Single and Dual Links?
All DVI formats (except DVI-A) are available in two connector types: single-link and dual-link.
DVI-D and DVI-I cables transmit information using TMDS, “Transition-Minimized Differential Signaling.”
The difference between single and dual-link connectors is that single-link connectors use one TMDS transmitter while dual-link connectors use two.
Dual-link DVI connectors also have more pins than their single-link counterparts. This difference increases their power, speed, and signal quality during transmissions.
Dual-link connectors can display higher resolutions too. For example, while a single-link DVI displays 1920 × 1200 resolution, a dual-link DVI displays up to 2560 × 1600.
Differences Between DVI-A, DVI-D, and DVI-I
The DVI interface has 29 pins total. It has an 8 × 3 pinout rectangle (24 pins) and five other adjacent pins (labeled C1 to C5).
However, the different DVI formats support different amounts of pins.
If you’re curious about the exact differences in their appearance, we’ll explain them in this section.
DVI-A format has the least number of pins. It supports 12 pins on the rectangular pinout and five adjacent pins.
DVI-A transmits analog signals with a slightly different configuration from VGA analog signals (VGA connectors have 15 pins).
The DVI interface is primarily for digital systems, while VGA is the accepted standard for analog transmissions. Hence, DVI-A formats are somewhat rare.
DVI-D interfaces are more common than DVI-A. They have 19 pins (for single-link) and 25 (for dual-link).
The majority of their pins are present on the rectangular pinout; only one (C5) is in the adjacent position.
If you own a digital monitor, your DVI port is probably DVI-I or DVI-D. However, when it comes to male connectors (cable plugs), DVI-D is the most popular format in the market.
DVI-I connectors support both analog and digital transmissions. Therefore, it should be no surprise that they have the highest number of pins.
Single-link DVI-I has 23 pins, 18 on the rectangular pinout and all adjacent pins (C1 to C5). Dual-link DVI-I connectors have all 29.
DVI-I interface does not have to convert digital and analog signals because it can accept anyone. DVI-I ports can also work with DVI cables in any format.
DVI-I is the most common DVI port because it can accommodate all the other formats.
Most manufacturers build DVI ports with all 29 pinholes into their devices. However, this does not always mean that the device supports the DVI-I format.
Some manufacturers build it to help prevent you from breaking pins on your cable if you plug in the wrong cable format.
Check the user manual or the labeling on the port to confirm your device’s DVI format.
Below are a few things you should know about DVI cables:
The number of pinholes in a DVI port determines which cable fits or doesn’t fit. Also, recall that single-link connectors use fewer pins than dual-link connectors.
Hence, (within a DVI format) single-link cables can fit into dual-link ports (with pinholes to spare), while dual-link cables cannot fit into single-link ports.
You can use a DVI-A cable with DVI-A or DVI-I connector ports to transmit analog signals only.
DVI-D cables work with DVI-D and DVI-I connectors. However, a DVI-D port cannot support DVI-A and DVI-I cables because it doesn’t have holes for four of the analog pins present in both formats (C1 – C4).
DVI-I cables cannot fit into DVI-A or DVI-D ports because it has more pins than either of them can support. However, DVI-I ports have enough pinholes to support all three cable formats.
Considering all we’ve discussed, a DVI-D cable is the most convenient option for transmitting digital signals.
DVI vs VGA vs DisplayPort
VGA, DVI, and DisplayPort are very important connectors. In this section, we’ll explore how well they fare compared to each other.
The DisplayPort connector interface transmits digital audio and video signals from a source to display devices. In the hierarchy of digital interfaces, it follows closely behind the HDMI interface.
One commendable feature of the DisplayPort connector is the MST (Multi-Stream Transport). MST allows you to connect one source device to multiple display devices.
DisplayPort also supports high-resolution media; it can transmit 4K at 60Hz. The latest version (2.0) has a transfer speed up to 77 Gbps — it is popular among PC gamers.
VGA (Video Graphics Array) is one of the oldest transfer interfaces in use. It transmits only analog signals between connected devices.
Since VGA is the standard analog connector, you’ll find it on many PCs, TVs, and DVD players. It is strictly for video transmission alone.
The original native resolution for VGA was SD (640 × 480p), but subsequent versions of the interface display higher resolutions like WXGA, XGA, and SVGA. It also supports HD (1080p) if you’re prepared for some loss of image quality.
Comparison Between DVI vs VGA vs DisplayPort
|Image Resolution||Low (SD, WXGA, XGA, and SVGA)||High; up to (1920 x 1200p) and (2560 × 1600p)||Highest; supports HD resolutions up to 4K|
|Signal type||Analog||Analog and Digital||Digital|
|Signal quality||Often degraded by conversion, cable length, and crosstalk||Less susceptible to signal degradation||Can be degraded by cable length|
|Input Lag||Low||The lag time may increase due to signal processing||The lag time may increase due to signal processing|
|Efficiency||Only transfers video signals||Needs a different cable for audio||Can transmit video and audio signals|
|Hotplugging||Does not support hotplugging||Supports hotplugging||Supports hotplugging|
Does DVI-I support both digital and analog?
Yes, DVI-I supports digital and analog signals.
As the name implies, the DVI-I interface integrates both qualities of analog and digital video transmission.
It is better to buy a device with a DVI-I connector port. This way, you can plug in (and use) any cable format without breaking the pins.
Which DVI is analog?
DVI-A is the format responsible for transmitting analog video signals. It has 17 pins, and it does not have a dual-link version.
The DVI-A connector is quite rare, however. This rarity is because most analog systems use the standard analog interface (VGA) instead.
The DVI connector is superior to the VGA because VGA only transmits analog signals. However, it is not as good as the DisplayPort and HDMI connectors.
If you have a DVI system, we advise that you identify its format before buying a cable. Look through the specifications in your device’s user manual to find its format.
If you don’t have a manual, this article contains information to help you identify your device’s format.