Image Quality & AA

When it comes to image quality, the big news from NVIDIA for Fermi is what NVIDIA has done in terms of anti-aliasing of fake geometry such as billboards. For dealing with such fake geometry, Fermi has several new tricks.

The first is the ability to use coverage samples from CSAA to do additional sampling of billboards that allow Alpha To Coverage sampling to fake anti-alias the fake geometry. With the additional samples afforded by CSAA in this mode, the Fermi can generate additional transparency levels that allow the billboards to better blend in as properly anti-aliased geometry would.

The second change is a new CSAA mode: 32x. 32x is designed to go hand-in-hand with the CSAA Alpha To Coverage changes by generating an additional 8 coverage samples over 16xQ mode for a total of 32 samples and giving a total of 63 possible levels of transparency on fake geometry using Alpha To Coverage.

In practice these first two changes haven’t had the effect we were hoping for. Coming from CES we thought this would greatly improve NVIDIA’s ability to anti-alias fake geometry using cheap multisampling techniques, but apparently Age of Conan is really the only game that greatly benefits from this. The ultimate solution is for more developers of DX10+ applications to enable Alpha To Coverage so that anyone’s MSAA hardware can anti-alias their fake geometry, but we’re not there yet.

So it’s the third and final change that’s the most interesting. NVIDIA has added a new Transparency Supersampling (TrSS) mode for Fermi (ed: and GT240) that picks up where the old one left off. Their previous TrSS mode only worked on DX9 titles, which meant that users had few choices for anti-aliasing fake geometry under DX10 games. This new TrSS mode works under DX10, it’s as simple as that.

So why is this a big deal? Because a lot of DX10 games have bad aliasing of fake geometry, including some very popular ones. Under Crysis in DX10 mode for example you can’t currently anti-alias the foliage, and even brand-new games such as Battlefield: Bad Company 2 suffer from aliasing. NVIDIA’s new TrSS mode fixes all of this.


Bad Company 2 DX11 Without Transparency Supersampling


Bad Company 2 DX11 With Transparency Supersampling

The bad news is that it’s not quite complete. Oh as you’ll see in our screenshots it works, but the performance hit is severe. It’s currently super-sampling too much, resulting in massive performance drops. NVIDIA is telling us that this should be fixed next month, at which time the performance hit should be similar to that of the old TrSS mode under DX9. We’ve gone ahead and taken screenshots and benchmarks of the current implementation, but keep in mind that performance should be greatly improving next month.

So with that said, let’s look at the screenshots.

NVIDIA GeForce GTX 480 NVIDIA GeForce GTX 285 ATI Radeon HD 5870 ATI Radeon HD 4890
0x 0x 0x 0x
2x 2x 2x 2x
4x 4x 4x 4x
8xQ 8xQ 8x 8x
16xQ 16xQ DX9: 4x DX9: 4x
32x DX9: 4x DX9: 4x + AAA DX9: 4x + AAA
4x + TrSS 4x DX9: 4x + TrSS DX9: 4x + SSAA  
DX9: 4x      
DX9: 4x + TrSS      

With the exception of NVIDIA’s new TrSS mode, very little has changed. Under DX10 all of the cards produce a very similar image. Furthermore once you reach 4x MSAA, each card producing a near-perfect image. NVIDIA’s new TrSS mode is the only standout for DX10.

We’ve also include a few DX9 shots, although we are in the process of moving away from DX9. This allows us to showcase NVIDIA’s old TrSS mode, along with AMD’s Adapative AA and Super-Sample AA modes. Note how both TrSS and AAA do a solid job of anti-aliasing the foliage, which makes it all the more a shame that they haven’t been available under DX10.


Click to Enlarge


Click to Enlarge

When it comes to performance, keep in mind that both AMD and NVIDIA have been trying to improve their 8x MSAA performance. When we reviewed the Radeon 5870 back in September we found that AMD’s 8x MSAA performance was virtually unchanged, and 6 months later that still holds true. The performance hit moving from 4x MSAA to 8x MSAA on both Radeon cards is roughly 13%. NVIDIA on the other hand took a stiffer penalty under DX10 for the GTX 285, where there it fell by 25%. But now with NVIDIA’s 8x MSAA performance improvements for Fermi, that gap has been closed. The performance penalty for moving to 8x MSAA over 4x MSAA is only 12%, putting it right up there with the Radeon cards in this respect. With the GTX 480, NVIDIA can now do 8x MSAA for as cheap as AMD has been able to

Meanwhile we can see the significant performance hit on the GTX 480 for enabling the new TrSS mode under DX10. If NVIDIA really can improve the performance of this mode to near-DX9 levels, then they are going to have a very interesting AA option on their hands.

Last but not least, there’s anisotropic filtering quality. With the Radeon 5870 we saw AMD implement true angle-independent AF and we’ve been wondering whether we would see this from NVIDIA. The answer is no: NVIDIA’s AF quality remains unchanged from the GTX200 series. In this case that’s not necessarily a bad thing; NVIDIA already had great AF even if it was angle-dependant. More to the point, we have yet to find a game where the difference between AMD and NVIDIA’s AF modes have been noticeable; so technically AMD’s AF modes are better, but it’s not enough that it makes a practical difference


GeForce GTX 480


GeForce GTX 285


Radeon 5870

Compute The Test
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  • Fulle - Tuesday, March 30, 2010 - link

    I wonder what kind of overclocking headroom the 470 has.... since someone with a 5850 can easily bump the voltage up a smidge, and get about a 30% overclock with minimal effort... people who tinker can usually safely reach about 1GHz core, for about a 37% overclock.

    Unless the 470 has a bit of overclocking headroom, someone with a 5850 could easily overclock to have superior performance, lower heat, lower noise, and lower power consumption.

    After all these months and months of waiting, Nvidia has basically released a few products that ATI can defeat by just binning their current GPUs and bumping up the clockspeed? *sigh* I really don't know who would buy these cards.
    Reply
  • Shadowmaster625 - Tuesday, March 30, 2010 - link

    You're being way too kind to Nvidia. Up to 50% more power consumption for a very slight (at best) price/performance advantage? This isnt a repeat of the AMD/Intel thing. This is a massive difference in power consumption. We're talking about approximately $1 a year per hour a week of gaming. If you game for 20 hours a week, expect to pay $20 a year more for using the GTX470 vs a 5850. May as well add that right to the price of the card.

    But the real issue is what happens to these cards when they get even a modest coating of dust in them? They're going to detonate...

    Even if the 470 outperformed the 5850 by 30%, I dont think it would be worth it. I cant stand loud video cards. It is totally unacceptable to me. I again have to ask the question I find myself asking quite often: what kind of world are you guys living in? nVidia should get nothing more than a poop-in-a-box award for this.
    Reply
  • jujumedia - Wednesday, March 31, 2010 - link

    with those power draws and the temps it reaches for daily operation i see gpu failure rates high on the gtx 480 and 470 as they are already faulty from the fab lab. Ill stick with ATI for 10 fps less. Reply
  • njs72 - Wednesday, March 31, 2010 - link

    I been holding on for months to see what Fermi would bring in the world of GPUs. After reading countless reviews of this card i dont think its a justifyable upgrade for my gtx260. I mean yeah the performance is much higher but in most reviews of benchmarks with games like Crysis this card barely wins against the 5870, but buying this card i would need to upgrade the psu and posibly a new case for ventilation. I keep loading up Novatechs website and and almost adding a 5870 to the basket, and not pre ordering gtx480 like i was intending. What puts me off more than anything with the new nvidia card is its noise and temps. I cant see this card living for very long.

    Ive been a nvidia fan ever since the the first geforce card came out, which i still have tucked away in a draw somewhere. I find myself thinking of switching to ATI, but read too many horror stories about their driver implementation that puts me off. Maybe i should just wait for Nvidia to refresh its new card and keep hold of my 260 for a bit longer. i really dont know :-(
    Reply
  • Zaitsev - Wednesday, March 31, 2010 - link

    There is an error with the Bad Company 2 image mouse overs for the GTX 480. I think the images for 2xAA and 4xAA have been mixed up. 2xAA clearly has more AA than the 4xAA image.

    Compare GTX 480 2x with GTX 285 4x and they look very similar. Also compare 480 4x with 285 2x.

    Very nice article, Ryan! I really enjoyed the tessellation tests. Keep up the good work.
    Reply
  • Ryan Smith - Wednesday, March 31, 2010 - link

    My master copies are labeled the same, but after looking at the pictures I agree with you; something must have gotten switched. I'll go flip things. Thanks. Reply
  • Wesgoood - Wednesday, March 31, 2010 - link

    Correction, Nvidia retained their crown on Anandtech. Even though some resolutions even on here were favored to ATI(mostly the higher ones). On Toms Hardware 5870 pretty much beat GTX 480 from 1900x1200 to 2560x1600, not every time in 1900 but pretty much every single time in 2560.

    That ...is where the crown is, in the best of the best situations, not ....OMG it beat it in 1680 ...THAT HAS TO BE THE BEST!

    Plus the power hungry state of this card is just appauling. Nvidia have shown they can't compete with proper technology, rather having to just cram everything they can onto a chip and prey it works right.

    Where as ATI's GPU is designed perfectly to where they have plenty of room to almost double the size of the 5870.
    Reply
  • efeman - Wednesday, March 31, 2010 - link

    I copied this over from a comment I made on a blog post.

    I've been with nVidia for the past decade. My brother built his desktop way back when with the Ti 4200, I bought a prefab with a 5950 ultra, my last budget build had an 8600 GTS in it, and I upgraded to the GTX 275 last year. I am in no way a fanboy, nVidia just has treated me very well. If I had made that last decision a few months later after the price hike, it would've definitely been the HD 4890; almost identical performance for ballpark $100 less.

    I recently built a new high-end rig (Core i7 and all), but I waited out on dropping the money on a 5800 series card. I knew nVidia's new cards were on the way, and I was excited and willing to wait it out; I expected a lot out of them.

    Now that they're are out in the open, I have to say I'm a little shaken. In many cases, the performance of the cards are not where I would've hoped they be (the general consensus seems to be 5-10% increase in performance over their ATI counterparts; I see that failing in many cases, however). It seems like the effort that nVidia put into the cards gave them lots of potential, but most of it is wasted.

    "The future of PC gaming" is right in the title of this post, and that's what these cards have been built for. Nvidia has a strong lead over ATI in compute and tessellation performance now, that's obvious; however, that will only provide useful if and when developers decide to put the extra effort into taking advantage of those technologies. Nvidia is gambling right now; it has already given ATI a half-year lead on the DX11 market, and it's pushing cards that won't be fully utilized until who-knows-when (there's no telling when these technologies will be more widely integrated into the gaming market). What will it do in the meantime? ATI is already on it's way to producing its 5000-series refresh; and this time it knows the competition's performance.

    I was hoping for the GTX 400s to do the same thing that the GTX 200s did: give nVidia back the high-end performance throne. ATI is not only competitive with it's counterparts, but it still has the 5970 for the enthusiast performance crown (don't forget Eyefinity!). I think nVidia made a mistake in putting so much focus into compute and tessellation performance; it would've been smarter to produce cards with similar die sizes (crappy wafer yields, anyone?), faster raw performance with tessellation/compute as a secondary objective, and more competitive pricing. It wouldn't have been a bad option to create a separate chip for the Tesla cards, one that focused on the compute performance while the GeForce cards focused on the rest.

    I still have faith. Maybe nVidia will work wonders with the drivers and producing performance we were waiting for. Maybe it has something awesome brewing deep within its labs. Or maybe my fears will embody themselves, and nVidia is crossing its fingers and hoping for its tessellation/compute performance to give it the market share later on. If so, ATI will provide me with my pair of cards.

    That was quite the rant; I wasn't planning on writing that much when I decided to comment on Drew Henry's (nVidia GM) blog post. I suppose I'm passionate about this sort of thing, and I really hope nVidia doesn't lose me after all this time.
    Reply
  • Kevinmbaron - Wednesday, March 31, 2010 - link

    The fact that this card comes out a year and a 1/2 after the the GTX 295 makes me sick. Add to that the fact that the GTX 295 actually is faster then the GTX 480 in a few benchmarks and very close in others is like a bad dream for nvidia. Forget if they can beat AMD, they can't even beat themselves. They could have did a die shrink on the GTX 295, add some more shadders and double the memory and had that card out a year ago and it would have crushed anything on the market. Instead they risked it all on a hair brained new card. I am a GTX 295 owner. Apperently my card is a all arround better card being it doesnt lag in some games like the 480 does. I guess i will stick with my old GTX 295 for another year. Maybe then there might be a card worth buying. Even the ATI 5970 doesn't have enough juice to justify a new purchase from me. This should be considered horrible news for Nvidia. They should be ashammed of themselves and the CEO should be asked to step down. Reply
  • ol1bit - Thursday, April 01, 2010 - link

    I just snagged a 5870 gen 2 I think (XFX) from NewEgg.

    They have been hard to find in stock, and they are out again.

    I think many were waiting to see if the GF100 was a cruel joke or not. I am sorry for Nivida, but love the completion. I hope Nvidia will survive.

    I'll bet they are burning the midnight oil for gen 2 of the GF100.
    Reply

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