Angle-Independent Anisotropic Filtering At Last

For a number of years now the quality of anisotropic filtering has been slowly improving. Early implementations from AMD and NVIDIA were highly angle-dependent, resulting in a limited improvement to image quality from such filtering. The angle-dependent nature lead to shimmering and other artifacting that was not ideal.

As of the previous generation of cards, the quality of anisotropic filtering had become pretty good. NVIDIA’s best filtering mode was pretty close to angle-independent, and AMD’s only slightly worse. Neither was perfect, but neither was bad either.


The Radeon HD 4890


The GeForce GTX 285

However so long as no one had an angle-independent implementation, there was room to improve. And AMD has gone there. The anisotropic filtering algorithm used by the 5000 series is now truly and completely angle-independent. There are no more filtering tricks being used.


The Radeon HD 5870: Perfection

As you can see, the MIP maps in our venerable D3D AF Tester are perfectly circular, the hallmark of an angle-independent implementation. With angle-independent filtering, this effectively marks the end of the filtering arms race. AMD has won, and should NVIDIA catch up in the future the two would merely be tied. There’s nowhere left to go for quality beyond angle-independent filtering at the moment.

AMD tells us that there is no performance hit with their new algorithm compared to their old one. This is a bit hard to test since we can’t enable the old algorithm on the 5870, but certainly whatever performance hit there is, is similarly minor. In all of the testing we’re doing today, you will see results done with 16x anisotropic filtering used.

What you won’t see however is a difference, particularly with our static screenshots. When discussing the matter, AMD noted that the difference in perceived quality between the old algorithm and the new one was practically the same. After looking at matters we find ourselves in agreement with AMD; we were not able to come up with any situations where there was a noticeable difference, beyond the obvious AF quality tests that are designed to identify such changes.

Regardless of the outcome, AMD deserves kudos for making angle-independent anisotropic filtering happen. It’s demonstrably perfect filtering with no speed hit versus the previous generation of filtering; making it in essence a “free” improvement in image quality, however slight the real-world results are. We’re always ready to get better image quality out of our video cards, after all.

More GDDR5 Technologies: Memory Error Detection & Temperature Compensation The Return of Supersample AA
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  • Wreckage - Wednesday, September 23, 2009 - link

    Hot, loud, huge power draw and it barely beats a 285.

    A disappointment for sure.
  • SiliconDoc - Thursday, September 24, 2009 - link

    Thank you Wreckage, now, I was going to say draw up your shields, but it's too late, the attackers have already had at it.
    --
    Thanks for saying what everyone was thinking. You are now "a hated fanboy", "a paid shill" for the "corporate greedy monster rip off machine", according to the real fanboy club, the ones who can't tell the truth, no matter what, and prefer their fantasiacal spins and lies.
  • Zstream - Wednesday, September 23, 2009 - link

    They still allow you to post?
  • yacoub - Wednesday, September 23, 2009 - link

    He's right in the first sentence but went all fanboy in the second.
  • Griswold - Wednesday, September 23, 2009 - link

    Not really, he's a throughbred fanboy with everything he said. Even on the "loud" claim compared to what previous reference designs vom ATI were like...
  • SiliconDoc - Wednesday, September 30, 2009 - link

    So if YOU compare one loud design of ati's fan to another fan and as loud ati card
    ( they're all quieter than 5870* but we'll make believe for you for now),
    and they're both loud, anyone complaining about one of them being loud is "an nvidia fanboy" because he isn't aware of the other loud as heck ati cards, which of course, make another loud one "just great" and "not loud". LOL

    It's just amazing, and if it was NV:

    " This bleepity bleep fan and card are like a leaf blower again, just like the last brute force monster core power hog but this **tard is a hurricane with no eye."

    But since it's the red cards that are loud, as YOU pointed out in the plural, not singular like the commenter, according to you HE's the FANBOY, because he doesn't like it. lol

    ULTIMATE CONCLUSION: The commenter just told the truth, he was hoping for more, but was disappointed. YOU, the raging red, jumped his case, and pointed out the ati cards are loud "vom" prior.. and so he has no right to be a big green whining fanboy...
    ROFLMAO
    I bet he's a "racist against reds" every time he validly criticizes their cards, too.
    ---
    the 5870 is THE LOUDEST ATI CARD ON THE CHART,AND THE LOUDEST SINGLE CORE CARD.
    --
    Next, the clucking rooster will whiplash around and flap the stubby wings at me, claiming at idle it only draws 27 watts and is therefore quiet.
    As usual, the sane would them mention it will be nice not playing any 3d games with a 3d gaming card, and enjoying the whispery hush.
    --
    In any case:
    Congratulations, you've just won the simpleton's red rooster raving rager thread contest medal and sarcastic unity award.(It's as real as any points you've made)

    Anyhow thanks, you made me notice THE 5870 IS THE LOUDEST CARD ON THE CHARTS. I was too busy pointing out the dozen plus other major fibboes to notice.
    It's the loudest ati card, ever.
  • GourdFreeMan - Wednesday, September 23, 2009 - link

    I thought the technical portion of your review was well written. It is clear, concise and written to the level of understanding of your target audience. However, I am less than impressed with your choice of benchmarks. Why is everything run at 4xAA, 16xAF? Speaking for most PC gamers, I would have maxed the settings in Crysis Warhead before adding AA and AF. Also, why so many console ports? Neither I, nor anyone else I personally know have much interest in console ports (excluding RPGs from Bethesda). Where is Stalker: Clear Sky? As you note its sequel will be out soon. Given the short amount of time they had to work with DX11, I imagine it will run similarly to Stalker: Call of Pripyat. Also, where is ArmA II? Other than Crysis and Stalker it is the game most likely to be constrained by the GPU.

    I don't want to sound conspiratorial, but your choice of games and AA/AF settings closely mirror AMD's leaked marketing material. It is good that you put their claims to the test, as I trust Anandtech as an unbiased review site, but I don't think the games you covered properly cover the interests of PC gamers.
  • Ryan Smith - Wednesday, September 23, 2009 - link

    For the settings we use, we generally try to use the highest settings possible. That's why everything except Crysis is at max quality and 4xAA 16xAF (bear in mind that AF is practically free these days). Crysis is the exception because of its terrible performance; Enthusiast level shaders aren't too expensive and improve the quality more than anything else, without driving performance right off a cliff. As far as playing the game goes, we would rather have AA than the rest of the Enthusiast features.

    As for our choice of games, I will note that due to IDF and chasing down these crazy AA bugs, we didn't get to run everything we wanted to. GRID and Wolfenstein (our OpenGL title) didn't make the cut. As for Stalker, we've had issues in the past getting repeatable results, so it's not a very reliable benchmark. It also takes quite a bit of time to run, and I would have had to drop (at least) 2 games to run it.

    Overall our game selection is based upon several factors. We want to use good games, we want to use popular games so that the results are relevant for the most people, we want to use games that give reliable results, and ideally we want to use games that we can benchmark in a reasonable period of time (which means usually having playback/benchmark tools). We can't cover every last game, so we try to get what we can using the criteria above.
  • GourdFreeMan - Thursday, September 24, 2009 - link

    Popularity and quality are strong arguments for World of Warcraft, Left 4 Dead, Crysis, Far Cry, the newly released Batman game... and *maybe* Resident Evil (though it is has far greater popularity among console gamers). However, HAWX? Battleforge? I would never have even heard of these games had I not looked them up on Wikipedia. In retrospect I can see you using Battleforge due to it being the only DirectX 11 title, but I still don't find your list of games compelling or comprehensive.

    To me *PC* gaming needs to offer something more than simple action to justify its cost of entry. In the past this included open worlds, multiplayer, greater graphical realism and attempts at balancing realistic simulation with entertaining game play. Console gaming has since offered the first two, but the latter are still lacking.

    It's games like Crysis, Stalker and ArmA II along with the potential of modding that attract people to PC gaming in the first place...
  • dvijaydev46 - Wednesday, September 23, 2009 - link

    Good review but it would be good if you could also add Steam and Cuda benchmarks. Now you have a common software Mediashow Espresso right?

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