Hardware Reference
In-Depth Information
Chapter 12. Video Hardware
Display Adapters and Monitors
Although the monitor (or video display) is as vital to a PC's user interface as the mouse and
keyboard, it is actually a latecomer to computing. Before CRT (cathode ray tube) monitors came into
general use, the teletypewriter was the standard computer interface—a large, loud device that printed
the input and output characters on a roll of paper. Early personal computers often used nothing more
than a panel of blinking light-emitting diodes (LEDs) for a display.
The first monitors used on computers displayed only text in a single color (usually green), but to users
at the time they were a great improvement, allowing real-time display of input and output data. Over
time, color displays were introduced, screen sizes increased, and LCD technologies moved from the
portable computer to the desktop. The latest trends reflect the increasing convergence of entertainment
and computer technologies.
Although modern video hardware is much more sophisticated than that of the past, you should still be
careful when selecting video hardware for your computer. A poor display can cause eyestrain or
otherwise significantly diminish the experience of using your PC.
The video subsystem of a PC consists of two main components:
•
Monitor (or video display)
—The monitor is a display device usually based on an LCD or LED
backlit panel, but it may also use CRT, plasma, DLP, or organic LED (OLED) technology.
•
Display adapter (also called the video card, graphics adapter, accelerated processing unit
(APU) or graphics processing unit [GPU])
—Although this often refers to an adapter card
plugged into a slot, the video adapter circuitry might also be built into the motherboard,
included as part of the motherboard's chipset, or built into the CPU itself. Although it sounds
strange, the circuitry is still called an adapter or card even if it is fully integrated into the
motherboard, chipset, or processor.
This chapter explores the range of PC video display adapters on the market today and the monitors
that work with them.
Note
The term
video
, as it is used in this context, does not necessarily imply the existence of a
moving image, such as on a television screen. Any circuitry that feeds signals to a monitor or
display is a video display adapter, regardless of whether it is used with applications that
display moving images, such as multimedia or videoconferencing software.
For this reason, video cards are sometimes referred to as
graphics cards
or
display adapters
.
Video Display Adapters
A video display adapter (aka video card) provides the interface between your computer and your
monitor and transmits the signals that appear as images on the display. Throughout the history of the
PC, there has been a succession of standards for video hardware that represents a steady increase in
screen resolution, color depth, and performance. The following list of standards can serve as an
