Hardware Reference
In-Depth Information
Chapter 12. Video Hardware
Display Adapters and Monitors
Althoughthemonitor(orvideodisplay)isasvitaltoaPC'suserinterfaceasthemouseand
keyboard, it is actually a latecomer to computing. Before CRT (cathode ray tube) monit-
ors 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 re-
flect 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)
—ThemonitorisadisplaydeviceusuallybasedonanLCD
or LED backlit panel, but it may also use CRT, plasma, or DLP technology.
•
Display adapter (also called the video card, graphics adapter, or graphics process-
ing 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 or included as part of
the motherboard'schipset. Although it soundsstrange, the circuitry is still called an
ad-
apter
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
Theterm
video
,asitisusedinthiscontext,doesnotnecessarily implytheexistence ofamov-
ing image, such as on a television screen. Any circuitry that feeds signals to a monitor or dis-
play 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
.
