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Mike20078800GTX
06-27-08, 08:41 AM
Hello, I am one vista x64 ultimate and playing witcher on a samsung 226bw at 1680x1050 (normal gaming res for all my games)
T.G. for widescreengamingforum.com (tweaks to enable 16:10 resolution in tons of games)

I however have a question since I just installed nhancer.

What is the absolute best mode to be using with 8800GTX and vista 175.80

The choices are
Application Controlled (no way)
Off (I don't think so)
Multisampling 16xQ (zero slowdowns in witcher)
SuperSampling 2x2 (zero slowdowns in witcher)
SuperSampling 3x3 (minimal mouse lag present)
Supersampling 4x4 (major mouse lag present)
Combined 8xS (zero slowdowns in witcher)
Combined 16xS (minimal mouse lag "not much at all")
Combined 32xS (major mouse lag present)

For the sake of arguement lets say that I wanted the best smoothing for all of my games. Which AA mode is always best to be run with a single 8800GTX (quality wise)
This is combined with 16xAF Always and Transparency AA and nhancer high quality driver mode

Why is there so many modes?
Which one works best on a single 8800GTX for overall gaming detail? Forget incompatibilities, I can always switch modes should I ever encounter a problem. I want to know which is always recommended to be used with 8x00 and later video cards when there are no issues with software conflicts.

Thanks

walterman
06-27-08, 10:07 AM
Basically, there are 2 AA modes: MSAA & SSAA.

With SSAA, the whole screen is rendered 2 or 4 times bigger than the selected resolution (1280x1024 SSAA 2x2 = 2560x2048, 1280x1024 SSAA 4x4 = 5120x4096). The biggest problem is the speed (this mode eats insane bw & rop power), but, it fixes all the artifacts derived from the jaggies & bad texture filtering. In fact, when you use SSAA 2x2 & AF 16x, you are using 64x AF, and when you use SSAA 4x4 & AF 16x, 256x AF. Also, with this mode, you can run deferred shading. All the rendering techniques are compatible with this mode. After all, this is just an shrink.

MSAA, doesn't change the rendering resolution. In this mode, the card just renders extra 'fragments', in the edges of the polygons. This reduces the number of fragments that you need to generate, to draw your scene. So, this mode is usually fast. But, this mode doesn't fix the texture filtering problems, or specular reflections, or shimmering, ... and has problems with deferred shading techniques (UE3 games).

So, nvidia has several MSAA modes, several SSAA modes, and a combination of them.

MS 2x, 4x & 8x
SSAA 1x2, 2x1, 2x2, 4x4 (& more)

4xS does SSAA 1x2 + MS 2x
8xS does SSAA 1x2 + MS 4x
8xSQ does SSAA 2x2 + MS 2x
16xS does SSAA 2x2 + MS 4x
32xS does SSAA 2x2 + MS 8x

The CSAA modes, are an extension to the MSAA modes. They generate extra 'coverage' samples (z values), that are stored into the AA buffers. They combine MSAA 4 or 8x, with 4 or 8 coverage samples. They help to increase the AA quality, with little performance cost.

So, about your question, if you care about absolute image quality (without speed in mind), then SSAA 4x4 is your mode. This mode runs ultra slow even with old games.

The next mode is 16xS. This mode uses SSAA 2x2 (ultra hq texture filtering), and then MSAA 4x on each sample (helps to filter the jaggies much better). This mode runs ok in some modern games like HL2 & TRA.

Then, you need to drop to the MSAA (or CSAA) modes. The 16xQ mode is as slow as the 16xS, and the IQ is inferior. So, if you care about speed and quality, use the 16x CSAA mode. This mode runs great in modern games like Jericho or TRL. The performance hit is acceptable.

The problem in the non SSAA modes, is that the alpha textures are not filtered properly. To fix this problem, you can use the transparency AA flags (MTAA & STAA). MTAA works fast, and STAA offers the best filtering. Anyway, STAA causes a major performance hit in games like HL2:Ep2, and it isn't much faster than the standard SSAA modes.

As resume, if you want to play a modern game (except Crysis), use 16x CSAA, and if you are playing an old title, use SSAA 2x or 16xS.

Hope this helps.

Medion
06-27-08, 01:54 PM
Walterman, thanks for this information. my old 7900GTO had 8xS, and I used that mode when I could. However, my 9600GT only comes with:

2x
4x
8x
8xQ
16x
16xQ

Is there a way to enable to SSAA modes?

walterman
06-27-08, 02:26 PM
Is there a way to enable to SSAA modes?

Yes, i forgot to tell you. You need nHancer to unlock all the modes. :)

Remember to check Options->Show Experimental Modes