Image Quality – ATI vs. NVIDIA
The information provided here is a gathering of the image quality pages found in our graphic card reviews. Instead of rehashing this analysis each and every time we publish a GPU review, we will instead place it in its own article and link back to it whenever relevant.
What do we mean by image quality and why is it important? Well, the truth of the matter is that NVIDIA and ATI/AMD do things differently at both the hardware and software (driver) levels, and in the past this has caused much controversy with regards to overall image quality — video cards are not created equal.
Though in this article we’ll concentrate on anti-aliasing and anisotropic filtering, other factors can also have an impact on overall image quality. If you recall, just months after the Geforce 7 series launched much controversy over "texture shimmering" came to light. It was caused by using an overly aggressive mip map optimisations which contained a bilinear filtering method for some LOD transitions instead of full trilinear. ATI used a similar method, but NVIDIA’s was a far heavier optimisation that had a greater negative impact on image quality while boosting performance numbers – a very questionable tactic that potentially could lead to more positive reviews if one only looked at performance numbers and not at image quality – something that is all too common i’m afraid.
In many games, users reported texture shimmering at some mip transitions and a huge uproar followed. This issue, though greatly improved in later driver releases was never fully resolved. To this day we still have trilinear optimisation’s "on" as default, below is the latest driver for the 8800 series.
As already noted, this article isn’t going to delve into mip map transition quality, mainly as it’s been done to death now and to be honest, both camps have got there act together in this area. I’ve mentioned this only as an example of why every gamer who prides himself on buying the best hardware for the price should not dismiss image quality differences between GPU families when ready to press the buy button, and certainly should not ignore added features which improve on this mantra, especially when the competitor lacks a similar slider. So let’s have a look at the main GPU families today and see how they differ in terms of image quality and which ones lack the features we really shouldn’t ignore.