ati vs nv IQ

[coolpurplefan]

Originally posted by: Madellga
Correct 100%.

Even better, uses also Supersampling on Transparency Antialiasing. This cures 95% of Nvidias Shimmering.

For ATI, use HQ AF, turn AL OFF. This solves 90% of the shimmering. ATI lacks behind on Transparency.

The X1800/X1900 cards shimmer in different places than Nvidia's 7800/7900.

ATI shimmers more on trees, vegetation, walls. Nvidia more on floor patches.

Neither card is perfect. I tried both and picked Nvidia, for better behaviour (vegetation) and quieter solution. ATI has a high pitch fan noise under load.

Cool, thanks for that info. I wanted real-world info from a user of both cards. It`s a good thing my favorite game is UT2004, because I got a non-GT 6600 with my motherboard in a combo deal. But, I can`t wait to try the Purevideo thing. Does that work on any movie you can download?

 

[CaiNaM]

Originally posted by: 5150Joker

Originally posted by: CaiNaM

Originally posted by: WaTaGuMp
I see it also in WoW on my X850XT PE AGP and never thought anything about it really, I havent played a game in my life where the graphics were 100% perfect no matter what card I had.

true (saw it on my x800pro), however your 850xtpe doesn't have the HQ AF mode the x1x00 series have. the texture filtering IS better in some cases (only had the card for a day so haven't compared alot of games), but imo nowhere near the difference some ppl on this forum try to convince others of.

What kind of monitor do you have? Secondly the HQ AF is better in ALL cases not just some because it's angle independent. Play a game with angles in the terrain like BF2 and you will notice a difference right away. In fact I'll be getting a 7800 or 7900 go for my XPS 2 pretty soon, I'll gladly do an uncompressed FRAPS comparison to highlight the differences. I currently have a 6800 Go Ultra which I could use but that card actually does filtering better than the 7800/7900 cards do.

i have an lcd (on both the ati and nv pc's) so limited to 1280. since i'm limited, i run with AA/AF/Tex Qual all as high as i can go (easily on done on the XT, not so much on the GT/GS).

I just ran BG2 on my XT earlier today, and honestly I was not impressed. Can't compare directly becauze don't have BF2 on the other pc, so maybe my memory is borked, lol. will have to do some more comparisons this weekend when i have some time.

Originally posted by: coolpurplefan
Cool, thanks for that info. I wanted real-world info from a user of both cards. It`s a good thing my favorite game is UT2004, because I got a non-GT 6600 with my motherboard in a combo deal. But, I can`t wait to try the Purevideo thing. Does that work on any movie you can download?

I will say that avivo > purevideo in most respects (and unlike the case with nvidia, you don't have to buy anything from ati to make this work), but for the avg user they will provide similar experiences. tho many video players, codecs, settings, etc.. the industry certainly need some consolidation in this area.

 

[Pete]

Originally posted by: CaiNaM

Originally posted by: wizboy11
n00b question, when you refer to shimmering, what are you talking about (making sure it's the right thing , and the thing i'm thinking of).

well, i believe it usually refers to mipmap transitions? usually refers to a faintly visible line that's kind of boxed around you and follows you wherever you go... that's not the effect i'm noticing in WoW tho.. it's kind of al over... hard to describe.

They're two separate things.

Texture shimmering looks like pixel popping or sparkling. This should be evident all over the screen. It's basically not enough filtering to avoid a pop or sparkle when a pixel's underlying texture changes abruptly. (With NV, forcing LOD clamp to zero in the CP should help with misbehaving games. With both NV and ATI, forcing texture quality to High in the CP/CCC should help.) This is what ppl are talking about with WoW.

(I believe a similar thing is happening with shaders and specular maps, for example with the shiny floor tiles in CSS Dust: no or not enough filtering. Edit: Actually, SSAA can help with both this and texture shimmer, so NV's mixed 8xAA mode is useful for single cards. I think all SuperAA and SLI AA modes help, too, in that they all incorporate some degree of SSAA.)

MIP-map transitions like with bilinear or maybe bri/trylinear filtering is a generally horizontal line or lines in screenspace that's fixed relative to your viewpoint and at which (in front and behind) you can see a distinct difference in texture clarity/blurriness. It's most obvious in flat, repeated road textures, like here. The various colors are the MIP-maps, and the transition is where two colors meet. Brilinear is an abrupt transition b/w MIP-maps. Trilinear is a smooth transition that filters across MIP-maps. Variations, like bri- and try-linear, are meant to emulate trilinear but with fewer samples, so with a lower performance penalty. On that page, "aggressive" looks like almost basic bilinear and "application" looks like trilinear; "balanced" is probably brilinear (IIRC). You can see what AF does is push the MIPmaps (and the lower-res textures in them) further away from you.

Edit: Although, yeah, all are caused by underfiltering, and texture shimmer can be a result of less-than-full trilinear leading to less-than-full filtering across MIP-maps. I was just making a distinction b/w the MIP transitions normally most visible on the ground and the general texture shimmer normally visible all over the scene. Here's another description of the problem, with pics.

 

[VERTIGGO]

another strange thing about these anomalies is that some games like DOD:S require Catalyst AI to fix, and sometimes like BF2 the AI turns off AA. Also, in DOD:S the rock textures were drastically affected by the LOD bias.

 

[CaiNaM]

Originally posted by: Pete

Originally posted by: CaiNaM

Originally posted by: wizboy11
n00b question, when you refer to shimmering, what are you talking about (making sure it's the right thing , and the thing i'm thinking of).

well, i believe it usually refers to mipmap transitions? usually refers to a faintly visible line that's kind of boxed around you and follows you wherever you go... that's not the effect i'm noticing in WoW tho.. it's kind of al over... hard to describe.

They're two separate things.

Texture shimmering looks like pixel popping or sparkling. This should be evident all over the screen. It's basically not enough filtering to avoid a pop or sparkle when a pixel's underlying texture changes abruptly. (With NV, forcing LOD clamp to zero in the CP should help with misbehaving games. With both NV and ATI, forcing texture quality to High in the CP/CCC should help.) This is what ppl are talking about with WoW.

(I believe a similar thing is happening with shaders and specular maps, for example with the shiny floor tiles in CSS Dust: no or not enough filtering. Edit: Actually, SSAA can help with both this and texture shimmer, so NV's mixed 8xAA mode is useful for single cards. I think all SuperAA and SLI AA modes help, too, in that they all incorporate some degree of SSAA.)

MIP-map transitions like with bilinear or maybe bri/trylinear filtering is a generally horizontal line or lines in screenspace that's fixed relative to your viewpoint and at which (in front and behind) you can see a distinct difference in texture clarity/blurriness. It's most obvious in flat, repeated road textures, like here. The various colors are the MIP-maps, and the transition is where two colors meet. Brilinear is an abrupt transition b/w MIP-maps. Trilinear is a smooth transition that filters across MIP-maps. Variations, like bri- and try-linear, are meant to emulate trilinear but with fewer samples, so with a lower performance penalty. On that page, "aggressive" looks like almost basic bilinear and "application" looks like trilinear; "balanced" is probably brilinear (IIRC). You can see what AF does is push the MIPmaps (and the lower-res textures in them) further away from you.

Edit: Although, yeah, all are caused by underfiltering, and texture shimmer can be a result of less-than-full trilinear leading to less-than-full filtering across MIP-maps. I was just making a distinction b/w the MIP transitions normally most visible on the ground and the general texture shimmer normally visible all over the scene. Here's another description of the problem, with pics.

that's by far the best explanation i've seen on these boards in some time, if not ever. thx pete

 

[Pete]

Ha! I just hope it's right. You're welcome, if it is.