Hercules 3D Prophet All In Wonder 8500 DV architecture
ATI R200 GPU (aka Radeon 8500)

The Hercules 3D Prophet All In Wonder 8500DV is powered by ATI’s most powerful GPU: the R200. The R200 chip, announced in October 2001, is engraved in 0.15µ and includes 60 million transistors. This compares to the Pentium 4 Northwood’s 55 million transistors. At the speed level, the R200 chip that powers the Hercules 3D Prophet All In Wonder 8500DV is downclocked compared to other Radeon 8500 boards: the GPU runs at 230 MHz while the 64 MB of memory is clocked at 190MHz.

• 60 million transistors

• 0.15µ engraving process

• GPU clocked at 230 MHz

• DDR 128bits memory clocked at 190 MHz

• 2x 400 MHz RAMDAC

• AGP 2x/4x

• SmartShader Technology

• HyperZ II Technology

• HSR (hardware surface removal) Support

The theoretical performance of the chip are as follow: 

• Bandwidth: 7.36 GB/s

• 4 pixel pipelines

• 2.76 GTexels/s

TruForm

   The TruForm feature of the ATI Radeon 8500 is a way to implement a new kind of primitives known as ‘high order surfaces’ into 3D games that support DirectX 8.0 or the OpenGL library. The Radeon 8500 supports the N-Patches High Order Surfaces technique. A normal triangle has three vertices and one normal for each of its vertices. The normal is generally used to define the reflection angle of the lightening sources. With TruForm the GPU will use the normals to transform a flat triangle into a curved surface thus enhancing the realism levels of most games. This process is also known as tesselation. The side effects of this method are that it costs bandwidth and generates some artifacts in some scenes (not all triangles have to be curved). Indeed if this technology consumes less bandwidth than doing the same thing by sending to the GPU an important numbers of high quality triangles, it stills costs bandwidth because the pipeline will be clogged up by small triangles that have to be handle by the GPU.

SmartShader

As every decent DirectX 8.1 optimized GPU, the ATI Radeon 8500 supports both pixel and vertex shaders and this feature are known as SmartShader. First you have to know what a Vertex is: a vertex is the corner of the triangle where two edges meet, and thus every triangle is composed of three vertices. A vertex usually carries information, like its coordinates, weight, normal, color, texture coordinates, fog and point size data. A Shader is a small program that executes mathematical operations to alter data so a new vertex emerges with a different color, different textures or a different position in space. Vertex Shaders are run by the GPU (so it doesn't consume CPU horsepower) to act on triangles’ top (vertices: it concerns every polygon shape) associated data for the Vertex Shaders or on the pixels for the Pixels Shaders.  

Now let's see the Pixel Shaders. If every 3D scene is composed of pixels generated by Pixels shaders, the Radeon 8500’s Pixel Shaders will convert a set of texture coordinates (s, t, r, q) into a color (ARGB), using a shader program. Pixel shaders use floating point math, texture lookups and results of previous pixel shaders. A pixel shader can execute programmed texture address operations on up to six textures and then run eight freely programmed instructions of texture blending operations that combine the pixel's color information with the data derived from the up to four different textures. Then a combiner adds specular lighting & fog effects to make the pixel alpha-blended, defining its opacity. Since the Hercules 3D Prophet All In Wonder 8500DV supports revision 1.4 of the Pixel Shaders, the SmartShader is able to use up to six texel-inputs per pixel shader program and supports long programs with up to 22 instructions. That way the Radeon 8500 features full support for technologies like Per-Pixel Phong Shading, Horizon mapping or Bump mapping combinations.

HyperZ II

   The ATI Radeon 8500 includes several features dedicated to save memory bandwidth in order to boost rendering performance. The memory controller of the Radeon 8500 divides the 128 bit memory interface in two, using two 64 bit channels to make data transfers more efficient.  

The HyperZ II engine combines three features aimed to save this precious bandwidth: Hierarchical Z, Z-Compression & Fast Z Clear. The Hierarchical Z detects hidden pixels in a scene so those pixels aren’t processed in order to speed up rendering time. It works with blocks of 16 pixels thus it can detect small hidden surfaces. The Z-Compression technology is a non destructive compression algorithm dedicated to Z data. Finally the Fast Z clear method quickly erases the Z buffer without the need to write a 0 for each pixel.

Charisma Engine II

   The Radeon 8500 includes a transform & lighting engine. Since a majority of games still use this process (rather than pixel and vertex shaders), the TL engine of the Radeon 8500 has been streamlined to make it extremely powerful (over 60 Mtriangle/s).

Pixel Tapestry II

   Under the ‘Pixel Tapestry II’ name lies the pixel rendering unit of the Radeon 8500. It consists of four pipelines that can apply three texels per pixel per clock while 6 texels can be applied per pass. The Hercules 3D Prophet All In Wonder 8500DV offers an impressive 2.76 Gtexels/s fillrate.

SmoothVision

   The ATI Radeon 8500 includes a new sophisticated multi sampling full scene anti aliasing process. Unlike other anti aliasing methods, SmoothVision can be programmed by developers. Thus a game developer can choose the most appropriate pattern that will be used for the multi-sampling in order to make the scene as real and smooth as possible. More flexible, the SmoothVision engine allows up to 16 different programmable sample modes and up to 16 samples per pixel for its FSAA. Using 16 samples will be, of course, highly consuming thus developers have the opportunity to choose the most appropriate and effective FSAA method.

SmoothVision Direct3D & OpenGL settings (click to enlarge)

VideoImmersion II

   In the past few years, ATI’s graphics cards’ embedded MPEG2 hardware decoder has become a legendary component since its inception and introduction with the Rage 128. The Hercules 3D Prophet All In Wonder 8500DV performs a 100% hardware decoding of MPEG2 video streams thus saving the previous CPU power, opening new horizons for multitasking while watching DVDs. The Video Immersion II engine also supports Motion Compensation and iDCT technologies to enhance the visual quality of viewed DVDs.  

ATI’s proprietary de-interlacing algorithm has been enhanced: the engine dynamically selects for each pixel of an image the most appropriate “bob” or weave de-interlacing technique in order to provide a sharp result. The new Temporal Filtering feature is aimed to avoid problems with refresh rates: video sources are generally in 50 or 60Hz while computer screens are refreshed at 75Hz or higher thus phenomenon like image repetition or jittering can be experienced. By interpolating intermediary images, the Temporal Filtering synchronizes both the video source and screen refresh rates for an optimal result which is an unique technique never seen on competing graphics cards.