Hardware Reference
In-Depth Information
Figure 12.16. DisplayPort to DVI adapter, which works on MultiMode DisplayPort connectors.
When DisplayPort was released, many people wondered why we needed another digital display
interface when we already had DVI and HDMI. Unfortunately, those interfaces carry both technical
and licensing limitations that were preventing their universal adoption. DisplayPort is designed to
overcome not only the technical limitations, but especially the licensing constraints and fees that the
other interfaces brought along as baggage. The advanced technical capabilities of DisplayPort,
including its ability to work with the new Thunderbolt I/O technology, combined with the elimination
of licensing and its backward compatibility with existing interfaces, are likely to ensure its eventual
adoption throughout the PC marketplace.
TV Display Interfaces
When video technology was introduced, it was based on television. However, a difference exists
between the signals used by a television and those used by a computer monitor. In the United States,
the National Television System Committee (NTSC) established color TV standards in 1953. Some
other countries, such as Japan, followed this standard. Many countries in Europe, though, developed
more sophisticated standards, including Phase Alternate Line (PAL) and Sequential Couleur Avec
Mémoire (SECAM).
Table 12.15
shows the differences among these standards.
Table 12.15. Television Versus Computer Monitors
To display computer screens on standard TV or to record them to videotape, you can use the TV-out
connector on your video card or integrated motherboard video. TV-out is generally S-video or
composite video. The resolution that these devices display on a TV set or record on videotape often
is limited to VGA (640×480) or SVGA (800×600).
To connect your PC to an HDTV monitor, it is preferable to use a digital signal via a DVI, HDMI, or
DisplayPort connection. If your current video adapter only has analog VGA output, you'll want to
