Transparency AA, Purevideo, and HDTV

On of the problems with Multisample AA is its inability to correct aliasing within a polygon. One of the main new features that NVIDIA added to the G70 is a method to combat the most notorious problem associated with MSAA: antialiasing of transparent textures.

When transparency AA is enabled on a GeForce 7800 GTX, textures that make use of the alpha channel can be flagged to have either supersample or multisample AA performed inside the texture. This can help a great deal for features often implemented with transparent textures such as leaves, vegetation or chain link fences.

This affords an increased performance hit along with its higher image quality, but no longer will fences, bushes, and trees cause a marked decrease in image quality even while running 4xAA. We will explore the performance hit and quality of Transparency AA in our analysis of the hardware, but NVIDIA provides the option of running with either SSAA or MSAA in this mode. MSAA incurs less of a performance hit, but SSAA is higher quality. We are glad that the choice is left to the end user and would even prefer that we get the choice in how FSAA is performed as well.

With increasingly powerful hardware we can afford to "waste" some cycles on SS in order to achieve slightly higher image quality in game that are severely CPU bound. Check out our recent Insider Article on NVIDIA's upcoming introduction of a 16x AA mode for 7800 GTX SLI systems. We will test this mode as soon as NVIDIA offers a driver with support for it.

This time around, Purevideo has extended support for HD format acceleration. The 7800 GTX will now have support for spatial-temporal de-interlacing for HD content. This feature promises to make 1080i content look that much better on a PC. NVIDIA has also said that the 7800 GTX should support H.264, but have said that the driver will not have support until near year's end. As we have already seen an H.264 demo from ATI, and the lack of anything tangible from NVIDIA at this point is disappointing. We are hesitant to even mention NVIDIA's claimed "support" before we see it running on actual hardware (especially after the lacking and late Purevideo support for initial NV40 parts). This time around, we can expect more support for alternate video players from NVIDIA as they are working with InterVideo and Cyberlink.

Not tied to the 7800 GTX is NVIDIA's latest improvement on HDTV support in their 75 series drivers (also launching today). Over time support for fitting a PC's output to any HDTV has improved, but this latest update makes it that much easier to deal with. Providing sliders and a full screen underscan adjustment feature is long overdue, but we still wish modern hardware could provide a more fully featured plug and play environment for HDTV.

We will also be getting some Windows MCE extensions that make HDTV setups easier to configure as well. If the US can manage to keep broadcast flags off the law books, public support for and adoption of digital television services and computers as media center boxes will surely continue to grow and prosper.

No More Shader Replacement The Test, Card, and High Resolution
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  • Johnmcl7 - Wednesday, June 22, 2005 - link

    If they're too busy for the article, that's fair enough, the point is they should put it up when they've had time to check it over, rather than rush an article up that isn't ready to be published.

    John
  • IronChefMoto - Wednesday, June 22, 2005 - link

    Regarding the "shame on Anandtech" comments -- y'all ever think they were too busy sh*tting themselves at the performance of this card to really pay that much attention to the article? ;-)

    IronChefMorimoto
  • Johnmcl7 - Wednesday, June 22, 2005 - link

    The prices I've seen here in the UK for the 7800s here are around 400 pounds, the 6800 Ultras are currently around 300 pounds. So quite an increase over the NV40s but not unacceptable given the performance, I'm sure they'll come down in price once the early adopters have had their fill.

    John
  • yacoub - Wednesday, June 22, 2005 - link

    #26 - You must be new to the market, relatively speaking. I remember quite well the days when high-end new videocards were at MOST $400, usually $350 or less when they debuted. It was more than a year or two ago though, so it might have been before your time as a PC gamer.
  • rimshot - Wednesday, June 22, 2005 - link

    Not sure why the price is so high in North America, here in Aus you can get a 7800GTX for the same price as a 6800GT ($850AU).

  • nitromullet - Wednesday, June 22, 2005 - link

    "What no Crossfire benchies? I guess they didn't wany Nvidia to loose on their big launch day."

    Ummm... maybe because CrossFire was paper launched at Computex, and no one (not even AT) has a CrossFire rig to benchmark? nVidia is putting ATI to shame with this launch and the availability of the cards. Don't you think if ATI had anything worth a damn to put out there they would?

    All that aside... I was as freaked out as the rest of you by these benchmarks at first (well moreso than some actually, becuase I just pulled the $600 trigger last night on an eVGA 7800GTX from the egg). However, these graphs are clearly messed up, and some appear to have already been fixed. I guess someone should have cut Derek off at the launch party yesterday.
  • blckgrffn - Wednesday, June 22, 2005 - link

    Very disapointed at the fit and finish of this article. Anandtech is supposed to have the best one, not a half baked one :( I even liked HardOCP better even with their weird change the levels of everything approach - at least it has a very good discussion of the differences between MS and SS AA and shows some meaningful results at high res as well.

    Shame on Anandtech :(
  • fishbits - Wednesday, June 22, 2005 - link

    Good release.

    Can we get a couple of screen shots with the transparency AA?

    "Maybe this one of the factors that will lead to the Xbox360/PS3 becoming the new gaming standard as opposed to the Video Card market pushing the envelope."
    Yeah, because the graphics components in consoles don't require anything but three soybeans and a snippet of twine to make. They're ub3r and free! Wait, no, you pay for them too eventually even if not in the initial console purchase price. Actually I think the high initial price of next gen graphics cards is a sign of health for PC gaming. There are some folks not only willing to pay high dollars for bleeding edge performance, they're willing to pay even higher dollars than they were in the past for the top performers. Spurs ATI/Nvidia to keep the horsepower coming, which drives game devs to add better and better graphics, etc.

    "They only reveresed a couple of labels here and there, chill out. It's still VERY OBVIOUS which card is which just by looking at the performance!"
    Eh, I use benchmarks to learn more about a product than what my pre-conceived notions tell me it "ought" to be. I don't use my pre-conceived notions to accept and dismiss scientific benchmarks. If the benches are wrong, it is a big deal. Doesn't require ritual suicide, just fixing and maybe better quality control in the future.
  • Thresher - Wednesday, June 22, 2005 - link

    2x6800GT costs almost the same amount as this single card and gives up nothing in performance.

    The price of this thing is ridiculous.
  • rubikcube - Wednesday, June 22, 2005 - link

    Just wanted to say thanks for starting your benchmarks at 1600x1200. It really makes a difference in the usability of the benchmarks.

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