ATI's Late Response to G70 - Radeon X1800, X1600 and X1300
by Derek Wilson on October 5, 2005 11:05 AM EST- Posted in
- GPUs
High Quality AF
One of the greatest things about the newest high end hardware from NVIDIA and ATI is that advanced filtering features can be enabled at any resolution while still maintaining playable framerates. It may take developers a little while to catch up to the capabilities of the X1800 and 7800 lines, but adding value through advanced quality features is definitely a welcome path for ATI and NVIDIA to take. For this launch, ATI has improved their AA and AF implementations. We also have two brand new features: Adaptive AA and Area Anisotropic filtering.
Starting with Area Anisotropic (or high quality AF as it is called in the driver), ATI has finally brought viewing angle independent anisotropic filtering to their hardware. NVIDIA introduced this feature back in the GeForce FX days, but everyone was so caught up in the FX series' abysmal performance that not many paid attention to the fact that the FX series had better quality anisotropic filtering than anything from ATI. Yes, the performance impact was larger, but NVIDIA hardware was differentiating the Euclidean distance calculation sqrt(x^2 + y^2 + z^2) in its anisotropic filtering algorithm. Current methods (NVIDIA stopped doing the quality way) simply differentiate an approximated distance in the form of (ax + by + cz). Math buffs will realize that the differential for this approximated distance simply involves constants while the partials for Euclidean distance are less trivial. Calculating a square root is a complex task, even in hardware, which explains the lower performance of the "quality AF" equation.
Angle dependant anisotropic methods produce fine results in games with flat floors and walls, as these textures are aligned on axes that are correctly filtered. Games that allow a broader freedom of motion (such as flying/space games or top down view games like the sims) don't benefit any more from anisotropic filtering than trilinear filtering. Rotating a surface with angle dependant anisotropic filtering applied can cause noticeable and distracting flicker or texture aliasing. Thus, angle independent techniques (such as ATI's area aniso) are welcome additions to the playing field. As NVIDIA previously employed a high quality anisotropic algorithm, we hope that the introduction of this anisotropic algorithm from ATI will prompt NVIDIA to include such a feature in future hardware as well.
We sat down with the D3DAFTester to show the difference between NVIDIA and ATI hardware with and without the high quality mode enabled. Here's what we ended up with:
One of the greatest things about the newest high end hardware from NVIDIA and ATI is that advanced filtering features can be enabled at any resolution while still maintaining playable framerates. It may take developers a little while to catch up to the capabilities of the X1800 and 7800 lines, but adding value through advanced quality features is definitely a welcome path for ATI and NVIDIA to take. For this launch, ATI has improved their AA and AF implementations. We also have two brand new features: Adaptive AA and Area Anisotropic filtering.
Starting with Area Anisotropic (or high quality AF as it is called in the driver), ATI has finally brought viewing angle independent anisotropic filtering to their hardware. NVIDIA introduced this feature back in the GeForce FX days, but everyone was so caught up in the FX series' abysmal performance that not many paid attention to the fact that the FX series had better quality anisotropic filtering than anything from ATI. Yes, the performance impact was larger, but NVIDIA hardware was differentiating the Euclidean distance calculation sqrt(x^2 + y^2 + z^2) in its anisotropic filtering algorithm. Current methods (NVIDIA stopped doing the quality way) simply differentiate an approximated distance in the form of (ax + by + cz). Math buffs will realize that the differential for this approximated distance simply involves constants while the partials for Euclidean distance are less trivial. Calculating a square root is a complex task, even in hardware, which explains the lower performance of the "quality AF" equation.
Angle dependant anisotropic methods produce fine results in games with flat floors and walls, as these textures are aligned on axes that are correctly filtered. Games that allow a broader freedom of motion (such as flying/space games or top down view games like the sims) don't benefit any more from anisotropic filtering than trilinear filtering. Rotating a surface with angle dependant anisotropic filtering applied can cause noticeable and distracting flicker or texture aliasing. Thus, angle independent techniques (such as ATI's area aniso) are welcome additions to the playing field. As NVIDIA previously employed a high quality anisotropic algorithm, we hope that the introduction of this anisotropic algorithm from ATI will prompt NVIDIA to include such a feature in future hardware as well.
We sat down with the D3DAFTester to show the difference between NVIDIA and ATI hardware with and without the high quality mode enabled. Here's what we ended up with:
NVIDIA 7800 GTX AF
NVIDIA 7800 GTX AF
Mouse over to cycle images
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Wellsoul2 - Wednesday, October 5, 2005 - link
I really prefer ATI so this is a disappointment.The 1300 and 1600 are pretty weak.
Might as well keep my 9600XT versus the 1300 - Can still play HL2 with noAA/AF.
The only good thing is maybe the price will drop on the x800/850 line.
The X1800 seems like a good card but why pay that money.
Why bother with the shared memory cards? It's dumb.
Cookie Crusher - Wednesday, October 5, 2005 - link
grammar is actually spelled with an "a" ;)OvErHeAtInG - Wednesday, October 5, 2005 - link
Yes, I have a feeling it'll be one of those cases where they make some editions and fixes to the article. Not that horrible, come on - I do agree the graphs are confusing. More important than graphs of benches, though, for me is the examination of the new AA, the architecture, features etc. Which they did a fair job ofOne remark: the bulleted lists are missing the bullets ... e.g. on page 2 the list of new features.
bldckstark - Wednesday, October 5, 2005 - link
Yes, this is the worst article I have ever seen posted on Anandtech. Will Anandtech continue to be my first stop on my daily hardware fix? Yes. Will I ever make Toms Hardware my first stop again? No. JEEEEZ toms sucks now. If you want to complain about a site as a whole take a look at them. They actually posted articles about how to pick up chicks while gaming! Multiple articles! Good Lord.Houdani - Wednesday, October 5, 2005 - link
Agreed! They did do a nice analysis of the new architecture.Agreed! Where are the bullets? (page 2 feature list, page 7 games list).
tfranzese - Wednesday, October 5, 2005 - link
Everyone's always surpised by this. Why? They've done this countless times now as if it's acceptable. Seriously, don't post an article until it's done and have it proofread carefully before posting it. I honestly doubt your (Anandtech) editors are doing more than just skimming articles sometimes with the number of typos and gramatical errors I come across.I hope the quality goes back up, because it will eventually hurt your reputation.
tfranzese - Wednesday, October 5, 2005 - link
I'll add, Anandtech is almost always my first stop to read a breaking review. Unfortunately, truths such as that below could someday change that. Today, Tech Report had the better article.Not their worst article, but things should be improving - not getting worse.
AnandThenMan - Wednesday, October 5, 2005 - link
I agree. VERY WEAK REVIEW! Terrible. Honestly, what happened? Anandtech is usually much, much more with it. Disappointed.As for the R520, I think I'm like most people and just feel, meh.
misterspoot - Wednesday, October 5, 2005 - link
Since the X1800 SKUs will not have the AGP bridge available (PCI-E) only, that leaves the X1600XT to attempt to give us AGP users a performance boost.Sadly, the X1600XT performs barely on par with a GeForce 6600GT -- which can be had for $150. Then, looking at the performance of the X1600XT, and comparing it to the X850 XT-PE -- surprise surprise, the year-plus old X850 XT is considerably superior.
So if you're like me and built your box nearly 2 years ago, and have no choice but to buy an AGP part, it looks like the X850 XT-PE is going to be the highest performance part you can buy. Looks like I'll be grabbing one this weekend, so my performance in raids on Molten Core is drastically improved (runs a 6600GT at 1600x900 with minimum detail settings -- suffers from mid 20fps all the time while trying to tank).
DRavisher - Wednesday, October 5, 2005 - link
The review states: "With its 512MB of onboard RAM, the X1800 XT scales especially well at high resolutions,". From what I see it scales very poorly at high resolutions compared to the 7800GTX 256MB card. Just look at what happens in SC:CT and FarCry. The XT goes from having a substantial lead in 1600x1200 to being about equal with the 7800GTX at 2048x1536.