WHAT ARE THE DVI FORMATS ?
There are three types of DVI connections: DVI-Digital, DVI-Analog, and DVI-Integrated (Digital & Analog)
DVI-D - True Digital Video
DVI-D cablesDVI-A - High-Res Analog
are used for direct digital connections between source video (namely, video cards) and digital LCD (or rare CRT) monitors. This provides a faster, higher-quality image than with analog, due to the nature of the digital format. All video cards initially produce a digital video signal, which is converted into analog at the VGA output. The analog signal travels to the monitor and is re-converted back into a digital signal. DVI-D eliminates the analog conversion process and improves the connection between source and display.
DVI-A cablesDVI-I - The Best of Both Worlds
are used to carry a DVI signal to an analog display, such as a CRT monitor or an HDTV. Although some signal quality is lost from the digital to analog conversion, it still transmits a higher quality picture than standard VGA.
are integrated cables which are capable of transmitting either a digital-to-digital signal or an analog-to-analog signal. This makes it a more versatile cable, being usable in either digital or analog situations.
Like any other format, DVI digital and analog formats are non-interchangeable. This means that a DVI-D cable will not work on an analog system, nor a DVI-A on a digital system. To connect an analog source to a digital display, you'll need a VGA to DVI-D electronic convertor
; to connect a digital output to an analog monitor, you'll need to use a DVI-D to VGA convertor
WHAT ARE SINGLE AND DUAL LINKS ?
The Digital formats are available in DVI-D Single-Link
as well as DVI-I Single-Link
format connectors. These DVI cables send information using a digital information format called TMDS (transition minimized differential signaling). Single link cables use one TMDS 165Mhz transmitter, while dual links use two. The dual link DVI pins effectively double the power of transmission and provide an increase of speed and signal quality; i.e. a DVI single link 60-Hz LCD can display a resolution of 1920 x 1080, while a DVI dual link can display a resolution of 2048 x 1536.