Dual DVI is a Digital Visual Interface connector that contains 24 pins arranged in a grid-like rectangular format to its right-hand side. This is not to be confused with a dual display DVI, which contains two connectors. Dual DVI is also known as a Dual-Link, and it is available as a connector on a cable or an electronic device like a personal computer (PC) or high-definition television (HDTV).
The Digital Visual Interface, also known as Digital Video Interface, debuted in 1999. It was designed by the Digital Display Working Group (DDWG). This is an open industry consortium founded by seven consumer electronics companies: Intel® Corp., Fujitsu Ltd., International Business Machines Corp. (IBM®), Hewlett-Packard Company (HP®), NEC Corp., Silicon Image®, Inc. and Compaq Computer Corp., which merged with HP® two years later.
DVI was supposed to replace the Video Graphics Array (VGA) connector. VGA was — and as of 2011 still is — commonly used for connecting monitors to desktop PCs or as an external display connector for laptop PCs. In contrast with VGA, which transmits analog video signals, the appropriately named DVI is used for digital visual displays.
Dual DVI's pins are responsible for the passage of the digital video signals. Dual DVI has six more pins than Single DVI, or Single-Link DVI; the number of pins in a Single-Link connector is 18. The additional pins on the dual-link connector increases the bandwidth, which is the range of frequencies it needs to transmit the video signals.
As a consequence, Dual-Link DVI permits a higher graphic display resolution than Single-Link DVI. The graphic display resolution stands for the number of pixels that can fit on the display screen. The Single DVI can manage up to 1,920 by 1,200 pixels in resolution. The Dual DVI surpasses it with a maximum display quality of 2,560 by 1,600 pixels.
Another result of the Dual-Link DVI increased bandwidth is the ability of the signals to travel longer distances than that of the Single DVI. The established maximum cable length standard for DVI cables is about 16 feet (5 m). Some manufacturers, however, carry Dual DVI cables that are as long as 25 feet (about 8 m).
Dual DVI connectors, however, can transmit more than just digital video signals. They can accommodate analog singles as well — the same ones that VGA connectors carry. Thus, there are two types of Dual-Link connectors: DVI-Integrated (DVI-I) and DVI-Digital (DVI-D). DVI-I contains digital and analog video pins to accommodate either type of computer monitor. DVI-D, on the other hand, is solely for digital visual displays.