Technical data

ance of different current and previous-generation
graphics cards in the Tom’s Hardware VGA Charts:
CPU
The system CPU has quite a bit of influence on
the graphics card’s performance. Even though mod-
ern graphics processors no longer need any CPU
time for their calculations, the data they process has
to be prepared by the CPU and then transferred to
the card. Additionally, the CPU also must take care
of handling computer player AI, physics calculations
and sound, all at the same time.To be able to push
a fast graphics card to its limit, you’ll also need a
potent CPU.
Of course, the opposite case is just as true – a fast
processor won’t do any good if the graphics card is
limiting the frame rate. And the same also holds
true for the system memory, which can hold the
system back if it’s too slow, or if there isn’t enough
of it. In summary, the individual components need
to be well-balanced. A single weak component can
cripple the entire system.
Fortunately, there aren’t any bad choices where
the graphics interface is concerned.
The current standard is the AGP 8x
bus, which will gradually be sup-
planted by its successor, PCI
Express, over the coming months
and years. For now, don’t expect to
see any performance increases from
switching to the new bus, however!
If you’d like to read up on PCI
Express and its future role in the
graphics market, take a look at our
article here:
http://graphics.
tomshardware.com/graph-
ic/20040310/index.html.
FSAA and AF
The abbreviations FSAA and AF
stand for two methods of improving
the image quality in 3D games.
FSAA is short for Full Scene Anti
Aliasing, which is a technique for
smoothing the edges of 3D objects
within a scene. AF is shorthand for Anisotropic
Filtering, which is a filtering method applied to
textures on 3D objects to make them look crisper
and less washed-out, greatly enhancing image quali-
ty. Both FSAA and AF are
very demanding on graph-
ics processors, especially
when used in combination.
These features can usually
be enabled or disabl e d
t h rough the graphics drive r ’s
c o n t r ol panel. Some games
also let you enable them directly through the in-game
options menu , without the need for special softwa r e.
H o weve r, some games have tro u b le with FSAA, d u e
to peculiarities of the graphics engine they use. I n
these cases, l e a ving FSAA disabled is usually the better
c h o i c e , as image corruption can occur otherwise.
The advantages of FSAA become especially obvi-
ous on slightly slanted vertical object borders.
Anisotropic filtering results in much crisper tex-
tures.
Although the underlying principles are the same
everywhere, the technical implementation of these
techniques differs from company to company and
even from one card generation to the next. On
older graphics cards or newer low-end models,
FSAA can only be used to a limited extent; this is
usually either because the card’s performance is too
low to deal with the extra calculations, or because
it uses a slow or outdated FSAA method.There are
also a number of different AF methods that differ
both in calculation complexity and resulting image
quality.
Both FSAA and AF require a lot of computing
power and memory bandwidth. For this reason, ATI
and NVIDIA use heavily “optimized” versions of
these methods to achieve better results (higher per-
formance) while still offering greatly improved
image quality compared to the standard rendering
output.The heaviest optimization is done on the
anisotropic filtering implementations. As a result,
there are some cases in which a reduction in image
quality compared to the “correct” or “real” method
becomes visible. Unfortunately, both of the big
players like to use this method of tweaking too
much in order to try to win benchmark compar-
isons.Therefore, image quality and performance can
differ immensely between driver versions even on
the same card!
You can read up on the texture filtering “opti-
mizations” currently in use in the following article:
http://graphics.tomshardware.com/
graphic/20040603/index.html
8
Comparisons with older graph-
ics cards can be found in previ-
ous iterations of our VGA
Charts:
http://www.tomshardware.com/graph-
ic/20020418/index.html

http://www.tomshardware.com/graph-
ic/20030120/index.html

http://www.tomshardware.com/graph-
ic/20021218/index.html

http://www.tomshardware.com/graph-
ic/20031229/index.html

http://graphics.tomshardware.com/gra
phic/20041004/index.html