Specifications

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Chapter 15 Video Hardware
The Video Processor
The video processor, or chipset, is the heart of any video adapter and essentially defines the card’s
functions and performance levels. Two video adapters built using the same chipset often have many of
the same capabilities and deliver comparable performance. Also, the software drivers that operating
systems and applications use to address the video adapter hardware are written primarily with the
chipset in mind. You often can use a driver intended for an adapter with a particular chipset on any
other adapter using the same chipset. Of course, cards built using the same chipset can differ in the
amount and type of memory installed, so performance can vary.
Since the first VGA cards were developed, several main types of processors have been used in video
adapters; these technologies are compared in Table 15.10.
Table 15.10 Video Processor Technologies
Where Video
Processor Processing Relative
Type Takes Place Speed Relative Cost How Used Today
Frame-buffer Computer’s CPU. Very slow Very low Obsolete; mostly ISA video cards
Graphics Video card’s own processor. Very fast Very high CAD and engineering
coprocessor workstations
Graphics Video chip draws lines, Fast Low to All mainstream video cards; is
accelerator circles, shapes; CPU sends moderate combined with 3D GPU on
commands to draw them. current cards
3D graphics Video card’s 3D GPU (in Fast 2D Most price ranges All gaming-optimized video cards
processor accelerator chipset) renders and 3D depending on chipset, and almost all mainstream video
(GPU) polygons and adds lighting display memory, and cards
and shading effects as needed. RAMDAC speed
Identifying the Video and System Chipsets
Before you purchase a system or a video card, you should find out which chipset the video card or
video circuit uses or, for systems with integrated chipset video, which integrated chipset the system
uses. This allows you to have the following:
■ Better comparisons of card or system to
others
■ Access to technical specifications
■ Access to reviews and opinions
■ Better buying decisions
■ Choice of card manufacturer or chipset
manufacturer support and drivers
Because video card performance and features are critical to enjoyment and productivity, find out as
much as you can before you buy the system or video card by using the chipset or video card manufac-
turer’s Web site and third-party reviews. Poorly written or buggy drivers can cause several types of prob-
lems, so be sure to check periodically for video driver updates and install any that become available.
With video cards, support after the sale can be important. So, you should check the manufacturer’s Web
site to see whether it offers updated drivers and whether the product seems to be well supported.
The Vendor List on the disc has information on most of the popular video chipset manufacturers,
including how to contact them. You should note that NVIDIA (the leading video chipset vendor)
makes only chipsets, whereas ATI (the #2 video vendor) makes branded video cards and supplies
chipsets to vendors. This means a wide variety of video cards use the same chipset; it also means that
you are likely to find variations in card performance, software bundles, warranties, and other features
between cards using the same chipset.
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