Display Connectors: Past, Present, and Future
Of all the types of connectors, monitor connections seem to have the longest lifespan. It always surprises me when I unpack a Dell monitor to find the VGA cable pre-attached. What century is this again?
Systems supporting integrated graphics often still have VGA connectors. Most monitors shipping today still offer VGA as a connection as well, though we’re finally seeing some displays without that ancient analog connector. I see very few discrete graphics cards with VGA any longer, though most still ship with a DVI-to-VGA dongle should you need it.
DVI (digital visual interface) first appeared in 1999, while VGA emerged over a decade earlier, in 1987. However, both DVI and VGA will ride off into the sunset together in 2015. DVI was the first widely adopted digital connection for PC monitors, and will be superseded by DisplayPort.
DisplayPort seems redundant, given the existence of HDMI. But DisplayPort brings a few wrinkles to the table for PC monitors, wrinkles not available with HDMI. Licensing is one aspect--DisplayPort is licensed through the industry standards body VESA, and is royalty-free. With DisplayPort 1.2, you can daisy-chain up to two high-bandwidth monitors, and the standard will support DisplayPort hubs for connecting even more monitors. DisplayPort also supports bit rates up to twice the throughput of HDMI, enabling support for very-high-resolution displays.
DisplayPort can also carry audio signals, up to eight channels total, with an aggregate bandwidth of 49 megabits per second.
HDMI is familiar as an interface for HDTVs, but is also available on a wide range of PCs and graphics cards. HDMI 1.4a offers enough bandwidth to run a 1080p display at 120Hz, suitable for stereoscopic games and video. HDMI is also capable of carrying an audio signal, and most discrete graphics cards sold today can handle audio as well as graphics.
Mini-DisplayPort was originally popularized by Apple, but is included as part of DisplayPort 1.2. It’s common on current-generation graphics cards built with AMD Radeon HD 6000 and HD 7000 series graphics cards.
Mini-HDMI is less common on PCs, though you find it on consumer electronics devices such as digital cameras. However, you may find the connector on a few discrete graphics cards built with Nvidia 500 series GPUs. Typically, there will also be a mini-HDMI-to-HDMI dongle in the package.
Next: The Past and the Future