GeForce 6600 GT Reference Review

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Since the 6600 is basically a product based on its big brother the 6800, it does feature all goodies the 6800 has, including full DirectX 9.0c support. That also includes UltraShadow II, the new video architecture and of course Shader Model 3.

UltraShadow IILast year we got acquainted with NVIDIA's UltraShadow technology. Shadows, nothing that new you might say. Yet precise and accurate shadows are so important to a 3D scene. They contribute to the 3D scene's environment, it's a step closer to the real thing, I guess... except for performance and that's where UltraShadow II comes in. UltraShadow II allows the game programmer to define a bounded portion of the scene (often called depth bounds), which limits the calculation of lighting source effects to objects within that specified area. By limiting calculations to the area most affected by a light source, the overall shadow generation process is highly accelerated. Stenciled shadow volumes do not require texturing or color so UltraShadow II hardware can double the rendering horsepower to generate stenciled shadow volumes at up to twice the standard pixel-processing rate. Did you know that allows the highly shadow intensive Doom III to run 3 times faster in regards to shadow processing.

NV4x Video Architecture
Next to being a gaming card, starting with the GeForce Series 6 some high-quality video options become available also. First off, Series 6 is a fully programmable video processor; you can aqctually use it in paint programs or software like Adobe After Effects. And hey, this has the first ever on-chip GPU video encoder. Among the features are motion adaptive interlacing, integrated TV-Encoder, complete HDTV support (720p. 1080i, 480p, CGMS). We so need HDTV support here in Europe. Not only that but the NV40 now also can Decode and... Encode MPEG 1/2 and 4, and yes also real-time DiVX Decode/Encode. Now if someone can please release the software to take advantage of it.

Judging from a .pdf file I also noticed new decoding progress in media output quality. In the snapshots below the first image (with red circles) indicates the current state of video. In the next shot, the one with the green circle, we can see improvements now made available by NVIDIA.

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Inverse Telecine (3:2 Pull Down) Correction

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Motion Estimation

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Vertical Scrolling Text De-Interlacing
 

Shaders Model 3.0
If you program or play computer games or even recently attempted to purchase a video card, then you will have no doubt heard the terms "Vertex Shader" and "Pixel Shader".

The step from 2.0 towards 3.0 is a small one and most Shader Model 2.0 games can easily be upgraded towards Model 3.0, which means more performance. DirectX 9 is now updated and we are going to see more support for 3.0 Shaders. Is it a huge visual advantage over 2.0? Not even the slightest bit. Yet aAny technological advantage is always welcome and preferred over a previous generation development. The general consensus for developers is to use as low a shader version as possible. Shaders 3.0 will be used only in several critical places where it gives a performance boost.

Since I've started to ramble on about Shader technology I just realized that some of you do not even have a clue what I'm talking about. Sorry, that happens when you get a bit excited. Let's do a quick shader course.

What do we need to render a three dimensional object as 2D on your monitor? We start off by building some sort of structure that has a surface, that surface is built from triangles. Why triangles? They are quick to calculate. How's each triangle being processed? Each triangle has to be transformed according to its relative position and orientation to the viewer. Each of the three vertices that the triangle is made up of is transformed to its proper view space position. The next step is to light the triangle by taking the transformed vertices and applying a lighting calculation for every light defined in the scene. And lastly the triangle needs to be projected to the screen in order to rasterize it. During rasterization the triangle will be shaded and textured.

And now we finally get to the stage where we can explain Shaders. Vertex and Pixel shaders allow developers to code customized transformation and lighting calculations as well as pixel coloring functionality. Each shader is basically nothing more than a relatively small program executed on the graphics processor to control either vertex or pixel processing.

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Medal of Honor Pacific Assault demo - With Shader Model 3 enabled you can boost its performance a bit.

Shader Model 3.0 titles that we can expect soon or are here already: Lord of the Rings; Battle for Middle-Earth, Stalker, Vampire; Bloodlines, Splinter Cell X, Driver 3, Grafan, Painkiller, Far Cry and more...

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