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One of the features we hear a lot about in todays graphics industry is Anti-Aliasing. Without going too indepth into the hows and whys, the technology is basically the card's hardware performing several addition algorithms on an image before it reaches the display stage. These algorithms result in many of the jagged edges associated with low resolutions being reduced or even remove depending on the level of anti-aliasing chosen.
This image improving feature comes at a sizable cost in performance however, and is found to be particularly relative to bandwidth, those cards maintaining a higher bandwidth being the best anti-aliasing performers that is.
Anisotropic Filtering is a second much talked about feature, and as with Anti-Aliasing, aim to bring the user an overall improved image. This is basically an advanced texture filtering surpassing Tri-Linear in terms of quality. This is particularly important for games that emphasise distance, particularly first person shooters, whereby the texture at the foot of the 'character' would be much clearer and of a higher quality than that of a texture on a wall in the distance. Anisotropic filtering would render the textures in more detail, further away from a given point the higher you set it, again, at the cost of performance.
As displayed in the driver section previously, both these options are available via the control panel, for both Direct3D and OpenGL. What kind of performance hit these features impose upon the hardware however, the card being already limited by bandwidth is sure to be detrimental to the performance of the card.
I again turned to 3dMark 2001SE, and ran the default benchmark at both 1024x768 and 1280x1024, 1600x1200 wouldn't run with the chosen AA/AF settings. The Anisotropic Filtering level was set to 4x and the Anti-Aliasing level was set to 2x Quality Mode for a moderate increase in image quality, and the second test had Anisotropic Filtering set to 8x and the Anti-Aliasing level was set to 4x Quality Mode.
Anisotropic filtering and antialiasing performance
As you can see, the particularly hardware intensive requirements of Anti-Aliasing and Anisotropic Filtering cripples the All-In-Wonder 9000 Pro even at the cards golden 1024x768 setting with the lightest settings.
Past experience with numerous ATI cards however has taught me that unlike NVIDIA's method of Anisotropic Filtering, which is particularly demanding, ATI's methods in the past have resulted in minimal performance hits at all but the highest settings. Therefore, in light of this, I would assume the large performance hit in the previous test is due to the Anti-Aliasing and not the anisotropic filtering.
To bring a little clarity to the matter, following test was conducted at just 1024x768, with no Anti-Aliasing to investigate the performance hit the Anisotropic Filtering has on the card.
Anisotropic filtering performance
As predicted, the anisotropic filtering has a minimal performance hit on the card coming in at around 9%. When the Anti-Aliasing , albeit at a high setting, maintaining the anisotropic filtering setting of 8x, we see a huge performance drop.
I can conclude from these results that anti-aliasing is not an option worth considering on this card, it's simply too demanding, and if you are looking to use anti-aliasing, you consider a higher performing solution.
Anisotropic filtering performance was pleasing however, and should be considered an option if the use wishes to improve clarity and quality of textures and filtering.
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