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here is what I would like to know. IF in fact there is something broken when it comes to AA, which is just speculation at this point, why is the AA hit not consistent in all games? Look at the link below. In X3 the 2900 takes a pretty big hit with AA. But in splinter cell, its very small and consistent with the other cards.
http://www.dinoxpc.com/Tests/articol...sp?id=644&p=10
The 2900 performs AA resolve on the shaders. The back-end sends the data back up to the shaders over the ring-bus.Quote:
Originally Posted by gunit
Not every game uses many shaders. This is best seen by looking at the 1900 and the 1800. The 1900 has many more pixel shaders. In some games the 1900 beats the 1800, such as FEAR and BattleField 2149 (or whatever year). In other games they are equal.
If a game does not use a lot of shaders, there are many shaders left that can be used. X3 isn't that shader intensive, but Splinter Cell Chaos Theory is (HDR + SMR 3.0).
X3
1280: 113.7 -> 78.4 -> 0.7
1600: 102.1 -> 63.9 -> 0.6
2048: 81.2 -> 45.5 -> 0.55
In X3 we clearly see that when the res goes up, the shaders & ring-bus have more work to do, and the performance hit from enabling AA increases.
Splinter Cell
1280: 165 -> 140 -> 0.85
1600: 125 -> 108 ->0.86
2048: 83 -> 75 -> 0.9
In Splinter cell we actually see that when the res goes up, the performance hit from enabling AA decreases. Why is this? It could be that at 1280 the CPU is bottlenecked (let's assume not).
Another theory is that the at higher resolutions the shaders can not perform their work in a single pass, thus a second pass is needed. With the second pass a whole lot of shaders are left doing nothing.
This would also explain why X3 takes a small hit from increasing resolution (there are enough shaders to take care of the resolution increase), whereas splinter cell takes a huge dive when increasing resolution (not enough shaders).
At this point we have to marvel at the ingenious ATI design. You can either increase the resolution without taking a huge performance hit (X3), or you can increase AA without taking a huge performance hit. The downside of this is that games tend to be indoor/outdoor a lot, which means different situations require different strategies. Maybe in time we will see auto-adjusting cards.
That is the first thing that comes into my mind, so I may be completely insane and very wrong.
New driver do the magic.Quote:
Originally Posted by poullos
Careful GTX, because things are getting very closer with simple updates in a pre-release drivers :D
oh i see. can u explain why the XT performs so well in doom 3 and unreal 3 engine based games, beating the GTX even, but its very mixed bag in other engines. here is quake 4 for example, which I am happy to see since my next game purchase will be ETQW.
http://www.bit-tech.net/hardware/200..._hd_2900_xt/20
Here is the thing: doing AA in the shaders will take a large performance hit if there are no engine specific optimizations in drivers. Meaning, for every game engine, ATI has to specifically add some code to make AA work at appropriate speeds for each game.Quote:
Originally Posted by gunit
It does well in the doom engine because that is the first thing ATI started optimizing for, so I would expect it to. Having the freedom of doing AA in the shaders has its disadvantages, but it can also be a good thing if they fine tune performance.
Naturally, I wouldn't mind specific optimizations for each title as long as ATI can keep up with the games being released :D
:up:Quote:
Originally Posted by poullos
As the drivers mature and the games are better optimized to use the arch. of the HD 2900XT you will see better performance, you can count on it :). I say wait until 8.39/8.40 is matured to see what the HD 2900XT can really do. :yepp:
I'd like to see how the megatexture they're using in ETQW is going to perform with the R600. According to the fud monkey R650 is going to fix the flaws in R600 including the poor texturing performance.Quote:
Originally Posted by gunit
Well yes. ATI keeps going with 16 TMUs, but I think its time to step out of the dark ages and see the light.
Quote:
Originally Posted by poullos
nice News , all tests with WINDOWS VISTA and in company of heroes even beat the 8800GTX , im waiting for those drivers
regards
hiya mascaras yes if you find the 8.38 drivers before they are officially out please post on here link
I'm not mascaras, but heres what I found.Quote:
Originally Posted by GLENBOY
http://www.hardforum.com/showthread.php?t=1192537
I dont have the card so I cant confirm the validity of them however. I'm not even sure what OS version they run in, but heres a link anywho.
Wow 133 megs. Thats huge.
Recent numbers for UE3 engines show that there is less than a 5% FPS dip from enabling 4xAA & 16xAF. Until I see pictures & a video of the benchmark that was run I am in doubt these games are working correctly; it is simply too good to believe.Quote:
Originally Posted by gunit
Prey has a newer engine, your better of at looking at those numbers.
Offtopic: do you play ET too? (it's a free multiplayer game)
no, i only play games that are completely far fetched and have no basis in real life (tribes vengeance atm.) The prey numbers are also very good, with the 2900 solidly beating the GTS even with AA and high res. this is just the feeling i got from every review site, all the games based on doom 3 engine run very good on the 2900.Quote:
Originally Posted by Noobie
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Originally Posted by gunit
i just looked around those are in fact 8.38.
Tell me about it. I just want to play video games! :p:Quote:
Originally Posted by Sumanji
hmm drivers are making it much better but I think I'll still wait for R650...
i too going to wait for R650
i hope 2950XT stays at the same price point of 2900XT, or even cheaper.
and i do hope they release it around september, or ill have to go for R600
im downloading 8.38 beta for XP now , test tonight or tomorow
regards
I hope to see the same price too,but we'll never see that happen....EVER...if it's really supposed to be the GTX killer as promised,i think we won't be paying 400 bucks for it....:down:Quote:
Originally Posted by evolution21
the download link about 5 posts up isn't for the hd2900 its for the mobility range
yep 8.38 doesnt work , only 8.37.4.3 and 8.37.4.2
regards
PLEASE!!, give me a link to these. :up: :DQuote:
Originally Posted by mascaras
Quote:
Originally Posted by mascaras
Ehhm linky ;) One for Vista if its there.
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Originally Posted by Tom|Nbk
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Originally Posted by mascaras
read plsQuote:
Originally Posted by deathman20
Vista 8.38 RC2 here
Since card is already on the market and numbers speak louder than words Im closing this thread.
Please start new one in 3D section.