Graphics and Windows NT 4.0
A Diamond Multimedia White Paper

The professional's choice

The word workstation conjures up images of powerful machines in the hands of an elite few. In truth, most workstations are based on proprietary operating systems originating from a UNIX kernel, and tuned for high performance RISC processors. The UNIX/RISC workstation can be an overachiever when it comes to performance, but fall short when it comes to sharing resources with other computers. There are many instances where UNIX/RISC workstations sit side-by-side with a PC because they cannot lower themselves to do productivity tasks such as word processing or e-mail in a networked office environment.

As many companies struggle to create environments where the flow of data and the exchange of information between different computer users is simplified, UNIX/RISC workstations are being relegated to highly specialized tasks to make room for Microsoft's Windows NT. The Windows NT workstation is one route to seamless integration, and it has many of the features users have come to expect from robust UNIX systems. Windows NT also has the benefit of being a part of the world of Windows, and is supported by a long list of applications. For many companies Windows NT brings engineering and design departments into the corporate fold. For many others, Windows NT is an affordable step towards putting power graphics on the desktop.

Windows NT workstations run most MS-DOS and Windows 95 applications, but they also support multi-processor configurations without requiring a change to the operating system or application. This is particularly relevant to processor hungry graphics applications such as CAD, rendering, visualization, and virtual reality. By taking advantage of scaleable multi-processor systems, Windows NT workstations deliver performance on a par with specialist UNIX/RISC graphics workstations. In simple terms, Windows NT is an industrial strength version of Windows.

Intel has also helped secure a place for Windows NT among workstation users. The Intel Pentium Pro processor was designed specifically for the 32-bit operating environment of Windows NT. Pentium Pro processors use dynamic execution to achieve performance greater than ordinary Pentium processors. Dynamic execution combines three techniques to boost performance. First, the processor looks 30 instruction ahead and predicts bottlenecks in performance. This process is called multiple branch prediction and reduces the time the Pentium Pro system has to wait for instructions from software. Second, Intel boosts performance by doing speculative execution of instructions, and finally, data flow analysis to ensure the processor is working at maximum capacity. While the Pentium Pro uses all its resources to ensure Windows NT applications perform optimally, the graphics subsystem also has to perform at higher levels than we have come to expect in more traditional environments.

3D on Windows NT

Windows NT is one of the best platforms for graphics applications. Microsoft has adapted OpenGL, originally developed by Silicon Graphics, as an interface for graphics applications working on Windows NT. OpenGL is a high level API used by specialist graphics applications in animation, CAD, visualization, and virtual reality. On Windows NT, OpenGL adds high-end graphics functionality and performance, offering the same level of functionality as we have come to expect from Silicon Graphics workstations. Microsoft helped to pave the way to Windows NT for many applications by porting the highly regarded Softimage animation studio from Silicon Graphics workstations to Windows NT. For many creators of digital content in the highly competitive worlds of advertising and film, the existence of Softimage on Windows NT has proven the PC is ready for the big time.

OpenGL is attracting engineering and scientific applications too. While companies such as Autodesk and Bentley Systems have been using the Windows environment for many years, CAD applications such as Parametric Technology's Pro/Engineer, and EDS' Unigraphics are now finding an audience on Windows NT. The CAD market is the largest high-end graphics market for Windows NT. It is an area where the exchange of information is critical to success. The combination of OpenGL functionality and Windows NT's rich feature set is proving to be the right mix for the exacting demands of engineers and scientists.

Microsoft is bringing their consumer technology to Windows NT. DirectX, Microsoft's strategic set of APIs for multimedia entertainment software development under Windows, is migrating to Windows NT. The addition of DirectX functionality to Windows NT brings with it a wealth of content and development tools designed for Windows 95 entertainment software, and Internet applications. The combination of OpenGL and DirectX makes Windows NT a comprehensive platform for the creation of all digital media assets. This is increasingly important to companies as they leverage multimedia technology and the concept of the Intranet to create more dynamic and visual means of handling data.

The graphics prerogative

There is no doubting the power of a Windows NT/Pentium Pro workstation for graphics applications. To create a true workstation experience on the Windows NT platform users must adopt new graphics technologies designed to handle the functions of OpenGL. Most Windows NT OpenGL applications are memory hungry to an extent never before seen on the PC, and they mandate powerful graphics subsystems to store large texture maps, handle z-buffer memory, and double-buffered graphics at high resolutions.

Table 1: Some of the many graphics applications available under Windows NT

High-end Windows graphics accelerators usually top off at 4 Mbytes of frame buffer memory, whereas the Windows NT 3D graphics solution is going to need a full 8 Mbytes of frame buffer memory. OpenGL based graphics applications usually demand a minimum of 1280 x 1024 resolution, with 32-bit true color, to be double-buffered in the frame buffer memory. High-performance 3D applications such as Softimage and 3D Studio MAX require minimum texture memory in excess of 16 Mbytes, local to the graphics processor, and in precision CAD applications the need for z-buffer memory local to the graphics processor also demands 16 Mbytes of local memory.

To increase performance and make optimal use of memory, OpenGL graphics accelerators divide any memory, above the 8 Mbytes of frame buffer storage, between z-buffer and texture memories. Some may choose to make these memories physically separate, but this adds to the cost of the graphics subsystem, and limits its flexibility. Also, many high-end OpenGL applications are designed to take advantage of two full size computer displays. This requires a graphics subsystem which can handle two screens equally and integrate the Windows NT desktop across two monitors.

Ideally, an OpenGL accelerator should also be equipped with a geometry setup engine. One of the choking points in 3D is the heavy computation required to prepare polygonal data for rendering to the screen in real-time. The geometry engine is a triangle processor which calculates which faces of a 3D object are visible, the deflection of light from the surface, and the attributes of a visible surface. All these features would eat up a CPUs processing power, even a Pentium Pro. A geometry engine was previously only available on expensive workstations, but it can now be had on the Windows NT platform as part of a graphics subsystem. OpenGL accelerator cards for Windows NT systems are designed to offload the Pentium Pro of graphics mathematics and to render 3D graphics in real-time.

Productivity Systems

Most users working with graphics applications under Windows NT will require the performance and features they have come to expect from traditional Windows accelerators such as the Diamond Stealth 3D 3000. The trend in graphics acceleration is towards an entry­level OpenGL productivity subsystem, with a high level of traditional 2D functionality and performance. Graphics controllers which fall into this category are often the newer 3D GUI products designed for high resolution, true color Windows support, and Direct3D acceleration. The 3Dlabs designed Permedia NT chipset is one example of a controller for entry level OpenGL and Direct3D acceleration.

With the coming of Intel's AGP bus, entry-level OpenGL accelerators will be able to make effective use of a Pentium Pro's system memory to handle large texture maps and z-buffer information. For many casual graphics users, entry-level OpenGL accelerators are both fast and cost-effective for general use.

Graphics Workstations

In graphics critical applications, where the creation of graphics content is essential to the success of a business, dedicated graphics processing of the highest order is required. Windows NT graphics workstations for Softimage, 3D Studio MAX, Solid Edge, Pro/Engineer, and AutoCAD have to deliver performance and features to match much higher priced UNIX/RISC workstations. The demands placed on memory bandwidth by high-end animation and mechanical engineering software dictates the presence of a fully loaded OpenGL graphics subsystem. Such a system will use at least 8 Mbytes of high performance, dual ported VRAM for its frame buffer memory, and have at least 16 Mbytes of on-board DRAM memory for the storage of texture maps, and z-buffer information.

A user of high-end OpenGL applications under Windows NT will not reap the full benefit of the platform without a highly specified graphics subsystem. In fact, most high-end OpenGL applications will not perform adequately without a properly configured OpenGL accelerator. It is critical for users who invest in Windows NT workstations to ensure the graphics subsystem of such machines matches the expectations of the software. While a processor such as the Pentium Pro enables applications such as Softimage to work as well under Windows NT as they do on a Silicon Graphics workstation, the level of interactivity between the user and the application is determined by the performance of the graphics subsystem.

Diamond's Windows NT Strategy

Diamond Multimedia addresses both productivity users and graphics workstations for Windows NT. Diamond has a series of high performance Windows accelerators to meet the demands of Windows power users. The Fire GL line of products addresses the demands of graphics professionals who require full OpenGL acceleration, 8 Mbytes of VRAM frame buffer memory, and at least 16 Mbytes of DRAM texture and z-buffer memory. Furthermore, Diamond's Fire GL 2000 and 3000 graphics subsystems are equipped with a unique technology innovation which allows twin monitors to be working from the same Fire board. This saves PCI slots, and saves the purchase of a second board.

For entry level OpenGL applications, Diamond provides the Stealth 3D graphics subsystem. This highly tuned 3D GUI accelerators is one of the fastest 2D graphics accelerators in its class, and it provides a high level of 3D functionality for Windows NT graphics applications through either OpenGL or Direct3D. The Fire GL 1000 is part of a new generation of OpenGL acceleration products based on the 3Dlabs' Glint technology. Fire GL 1000 is an affordable solution, but for the best in OpenGL acceleration, and high performance graphics, users need to turn to the Fire GL 2000 and 3000. These are powerhouse boards when it comes to performance, but priced aggressively for creative, engineering, and scientific users. The choice between a productivity solution and a workstation solution for Windows NT is summarized in the table below.

Table 2: Choosing a Windows NT graphics solution

At Diamond, we have come to realize the Windows NT is an opportunity for our customers to move into a new realm of computing power. The Stealth 3D, and Fire product lines keep your graphics on the bleeding edge in this new world.