What does dual-link DVI actually mean?
As I’ve been searching around for information on the rate of adoption of DisplayPort (for an upcoming post), I’ve come across a lot of confusion on message boards where people think “dual link” DVI means using both of the DVI ports on your FireGL graphics card to drive one or two monitors. The name dual link, while technically accurate, is a misnomer for many consumers.
So what does dual link actually mean? “Dual Link” DVI use two TMDS digital signal transmitters and 8 wires to send data, while “single link” uses one TMDS digital signal transmitter and 4 wires. The Dual link DVI effectively doubles the power of transmission and provides an increase of refresh rates and signal quality. Specifically a DVI single link 60-Hz LCD can display a resolution of 1920 x 1200, while a DVI dual link 60-Hz LCD can display a resolution of 2560 x 1600.
If you look at the plug-ends of a single “dual link” cable, you see it actually has more pins packed in than standard single link DVI cables (18 vs 24 pins). In this case, more pins and wires in the cable translates to more bandwidth. Where this becomes slightly confusing is that on most of the current FireGL accelerators you will see two Dual Link DVI outputs. This means you can drive two high resolutions monitors, each up to 2560 x 1600.