Technical data

gaming resolution.The most popular higher resolu-
tions are 1280x1024 and 1600x1200. In the case of
classical CRT (cathode ray tube) monitors, the res-
olution can be selected freely, as long as it doesn’t
exceed the maximum possible physical resolution
supported by the screen.Things are more compli-
cated when TFT (thin film transistor, aka flat screen
or LCD) monitors are used, since these have fixed
resolutions.Any setting that differs from the moni-
tor’s native resolution requires that the image be
interpolated, meaning either shrunk or enlarged.
Depending on the model that is used, this can have
a noticeably adverse effect on image quality.
Therefore, it is a good idea to choose a graphics
card that offers good frame rates at your TFT’s
native resolution.
In addition to the resolution chosen, a card’s
frame rate will also depend to a great extent on the
game being run.The extensive use of complex
shaders in new games slows down many older cards
unacceptably, even if these same cards offer very
reasonable performance when running older titles.
Most PC games allow for a reduction in detail
level, thereby also reducing the number and com-
plexity of effects, but this of course has a negative
impact on the image quality and, consequently, on
the gaming experience.The most important factor
here is the DirectX support of both graphics card
and game, which should be on the same level (see
the section on DirectX Technology).
Benchmark Results
Since the performance of a card depends to such a
great extent on the game being played and the
selected resolution, a large number of combinations
must be tested to reach a conclusive verdict on a
card’s performance. Cards from different manufac-
turers may show different performance in the same
game.
This picture shows a typical benchmark table
from the THG VGA Charts. Here, the game
Doom3 was tested at a resolution of 1024x768 at
32-bit color depth. 4xFSAA and 8x anisotropic fil-
tering were enabled, and the quality setting “High”
was selected.
To determine a card’s in-game performance,
frame rate measurements are taken at distinctive
points in the game. Many titles offer a recording
feature for motion sequences, making it very easy
to take comparable measurements for a number of
cards. Some games measure the frame rate using a
built-in function, while others require additional
add-on utilities such as FRAPS. Another option for
benchmarking tests is using in-game cut scenes,
which are of course identical every time. Finally, for
games that don’t offer any of the choices above, the
only remaining option is to try to replicate the
same series of movements manually on every card.
The results found in the benchmark tables are
usually the average of several tests, s h owing the
average frame rate a card is able to sustain in a
g a m e.T h u s , a result of 60 fps means that the frame
rate may dip below and rise above that number at
d i f f e rent places in the game.
M i n i mum scores would be
m o re meaningful, but these
a re ve r y difficult to deter-
m i n e ; dips in frame rate can
be caused by in-game load-
ing or background activity of
the operating system, a n d
these fa c t o r s cannot be easily
re p l i c a t e d . T h e re f o re, t h e
average frame rate re m a i n s
the most meaningful measur-
ing standard .
Despite this, we can’t emphasize often enough
that you need to remember that these are indeed
average values. If a card only runs a game at an aver-
age of 25 fps, the game will show pronounced stut-
tering during its “slower periods” which may seem
to turn it into a slide show. In general, you should
be on the safe side with a card that pushes 60-100
fps in games – at the highest quality settings, of
course.
You can find a good overview of the perform-
THG Graphics Card
Buyers Guide
7