Technical data

ATI and NVIDIA support Linux with special drive r s .
Linux drivers can be found on ATI’s and
NVIDIA’s download pages.
Video Playback
Video playback and Media Player visualizations can
be accelerated by graphics cards, taking load off the
CPU.
As we mentioned near the beginning of the art i-
c l e, video can be played back on practically any
graphics card , as long as the correct codec is
i n s t a l l e d . Almost all graphics cards ava i l a b le today also
offer special video acceleration features that handle
effects such as resizing a video to fit a window, f i l t e r-
ing and the like.The more tasks the graphics pro c e s-
sor can handle, the less work is left to the CPU,
i m p roving overall perform a n c e . In the case of
HDTV videos using ve ry high re s o l u t i o n s , it is possi-
ble that the CPU alone isn’t up to the task of decod-
ing and playing back a video at all -- and this is
w h e r e the video processor can step in to help.
Video acceleration is also an important issue for
notebooks, as a CPU usually requires more power
than a graphics processor. As a result, a good video
acceleration will do its part in lengthening the run-
ning time of a notebook.Video acceleration fea-
tures also come into play when watching DVDs.
R e c e n t l y, both ATI and NVIDIA have put special
emphasis on video feature s , and practically eve r y new
generation of graphics pro c e s s o rs comes with extend-
ed video functionality.ATI groups together these
c a p a b i l i t i e s , which can be found in the new X800
and X700 line of card s , under the name “ F u l l S t r e a m
H D.” M o re information is ava i l a b le here :
http://www.ati.com/products/brochu
res/5639fullstreamWP.pdf.
NVIDIA has equipped its newest chip family, the
NV4x line, with a special, programmable video
processor.This ensures support even for future
video formats. Additionally, the video processor is
designed to take some of the burden off the CPU
when recording videos or during video encoding
processes. More detailed information is available
here: http://www.nvidia.com/object/feature_on-
chip-video.html.
#3 Performance
& Image Quality
Performance
The performance of a graphics card is normally
measured by its frame rate, which is expressed in
frames per second (FPS).The higher the frame rate
a card can support, the more fluid the gaming
experience will seem to the user. Essentially, a game
displays a sequence of individual images (frames) in
rapid succession. If they are output at a rate exceed-
ing 25 fps, then the human eye is usually no longer
capable of distinguishing the individual frames.
However, in fast-paced games, such as first person
shooters, even 25 fps will not be enough to make
the game and all movements seem fluid.The bar for
such games should be set at least at 60 fps.
Aside from features such as FSAA and AF (which
we will come to shortly), frame rate primarily
depends on the selected screen resolution.The
higher the resolution, the more pixels are available
to display the scene, making the resulting output
much more detailed. However, with increasing res-
olution, the amount of data that a graphics card has
to handle also increases, meaning greater demands
are placed on the hardware.
There are two important factors in assessing the
ability of a graphics processor to provide high
frame rate.The first is its pixel fill rate, which deter-
mines how many pixels can be processed per sec-
ond (megapixels per second).The second is memo-
ry bandwidth, which measures how quickly the
processor can read and write data from memory. In
both cases, the “more is better” mantra applies.
At higher resolutions, more pixels are available to
depict a more detailed image, as you can see in this
image.While only very rough details can be made
out at 800x600 (the small tree next to the Jeep), the
detail level is much higher at 1600x1200.
Today, 1024x768 pixels is considered the standard
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