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With the often confusing cables, connectors, and standards
to be encountered out there. Tell us what you think VGA cables, unless you know
for absolute certainty that you will only ever run a low-resolution device.
Even then, it is probably advisable to stick with Super VGA cables, to ensure
that the cable you purchase today will continue to work into the future. Visit
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technical articles, with each one focusing on a particular technology. Our goal
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feedback. Reply back to Pradeep@worldofcables.com and give us your thoughts. IBM’s next
standard of note was called "XGA", which offered a maximum resolution
of 1024 x 768 with 256 colors. It could also produce 640 x 480 resolutions with
what was at the time a stunning 65,536 colors.
Although it
would be a few years before IBM released another formal video standard, other
video card manufacturers quickly began producing cards that could support
higher resolutions and color depths than IBM’s VGA standard. These various
capabilities were informally called "Super VGA" modes, which over
time came to mean "anything better than 640 x 480 at 16 colors."
(Eventually, the Video Electronics Standards Association (VESA) helped consolidate
these disparate standards and produced a "Super VGA" standard
programming interface that included, among other things, a defined 800 x 600 at
16 colors resolution.)
developed the VGA standard are no longer appropriate for
modern resolutions. Most of us in the cable industry are careful to
differentiate between the informal terms "VGA cable" and "SVGA
cable," which have physically different constructions.
A traditional VGA cable was fairly
simple. It consisted of 14 or 15 28 AWG (28 gauge) wires in a jacket, with 15
pin connectors on either end. These cables, still in use today on older
equipment, are suitable for the relatively low resolutions of the original VGA
standard. However, it quickly became clear, as resolutions were increased, that
a new cable design was going to be necessary. Recognizing that the most
critical data flowing through the cable is the red, green, and blue color data,
super VGA cables (which are sometimes marketed as "XGA cables") were
designed to minimize any interference from compromising the signal along those
lines. Rather than just using a pair of wires (one for signal, one for ground)
for each color channel – as had previously been done with traditional VGA
cables – the newer SVGA cables were designed with three miniature coaxial wires
inside the main cable. (Coax cable is a broad term referring to any cable that
has a center pin delivering data, surrounded by insulating material and one or
more shields that provide grounding and mitigate external interference.)
Well-constructed SVGA cables are cable of carrying high resolutions (up to 2048
x 1536) at distances up to 100 feet without external amplification. When
purchasing these cables, you should always take care to purchase Super VGA
cables, not standard
Since that time, continued improvements in technology have
pushed resolutions higher and higher, with increasing color depths. Along with
these improvements has come a slew of acronyms to define them, which are shown
in the table below. In practice, most of these acronyms are rarely used, and
the terms "VGA" and "Super VGA" (or "SVGA") are
used instead.
So why does a cable company worry about different video
standards? Well, as one would expect, higher resolutions and color depths mean
more data going through a cable. In fact, the original VGA cables used when IBM
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| About the author |
Although many people use the term "VGA" casually to mean any modern high-resolution display (or video card), the term VGA – which stands for "Video Graphics Array" – has a very specific technical meaning. Developed by IBM, it was first introduced in 1987, and was used to describe a display with a resolution of 640 x 480, 16 colors (there were a few other modes it could display as well). It was, at the time, a considerable improvement over previous color graphics options. |
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