Introducing the SGI Visual Workstations for Windows NT
On January 11, SGI announced the new family of visual computing products that will revolutionize the Windows NT market: the Silicon Graphics 320TM and the Silicon Graphics 540TM visual workstations.
With these powerful Windows NT workstations, SGI leveraged nearly 20 years of technical expertise in visual computing to design a system architecture that provides the demanding performance and exceptional image quality that you and your applications require.
Key features of these new workstations include:
- Performance
- Hardware acceleration for industry-standard graphics and digital media APIs: OpenGL® 1.1,
DirectX (Direct3D, DirectDraw, DirectShow), GDI, QuickTimeTM,
Video for Windows®
- Differentiated system architecture with integrated features and high bandwidth
- Scalability to two or four Intel® processors
- OpenGL acceleration and image quality
- One-hundred-percent compatibility
- Full compatibility with Windows NT workstation-certified applications; all Win32 applications will run on this system natively
- One code base, one binary for all Windows NT hardware platforms
- New Graphics Software Development Kit (Graphics SDK) and Digital Media SDK
- Industry-leading price/performance
Suggested starting configuration for Silicon Graphics 320 Developer Station is 400 MHz Pentium® II,
256MB SDRAM, 10.1GB Ultra ATA hard drive, Silicon Graphics 1600SWTM flat panel display, and the Graphics Software Development Kit (Graphics SDK).
Starting price for Silicon Graphics 320 is $3,395, including 350 MHz Pentium II, 128MB RAM, and 6.5GB
Ultra ATA hard drive (SCSI optional); starting price for Silicon Graphics 540 is $5,995, including Cobalt
graphics, 450 MHz Pentium II XeonTM, 128MB RAM, and 9GB SCSI drive.
This article describes the attributes of the Silicon Graphics 320 and Silicon Graphics 540 visual workstations that
pertain to software and hardware developers.
Integrated Visual Computing Architecture
In an effort to deliver graphics performance, competitive Windows NT workstations generally rely on antiquated
architecture and optional graphics cards. Graphics and I/O in these systems are assembled to obtain an
approximation of a workstation. As a result, the systems typically perform poorly because high bit-rate devices are
still being plugged into a PC architecture.
SGI has designed an Integrated Visual Computing (IVC) architecture, where all primary workstation
features are integrated into the core logic of the motherboard. This design embeds the graphics acceleration into the
chipset and then teams the chipset with memory through a high-bandwidth connection. The chipset, referred to as the
Cobalt graphics chipset, is responsible for communicating directly to the Intel-based CPU and I/O subsystems as
well as the audio, video, network, and IEEE 1394 interfaces.
The graphics and digital media pipeline performance of the visual workstations benefits from the custom-designed
motherboard and ASICs. The biggest bandwidth improvement comes from the bus connection between the Cobalt
graphics and memory controller ASIC to the memory subsystem, which will have a peak bandwidth of 3.2GB per
second. This connection yields roughly six times the memory bandwidth of Intel's AGP 2X. The I/O ASIC has 10
times the I/O bandwidth of the normal PCI 32 bus--1.6GB per second versus 133MB per second. Additionally, the
IVC architecture supports two PCI 64 buses to take advantage of high-speed networking (FDDI and ATM) and faster
disk drives. At 266MB per second, the wider PCI 64 bus has twice the bandwidth of the PCI 32 bus.
The performance advantages of the visual workstations are realized in rendering large 3D models in the graphics
subsystem while streaming video into the system for processing. Much of the OpenGL pipeline is implemented in
the Cobalt chipset, which boosts performance over existing graphics cards. Conventional bottlenecks that exist on
the PCI bus will not be a factor with these systems. Figure 1 illustrates the differences between a PC's and the IVC architecture.
Figure 1: SGI Integrated Visual Computing Architecture
Figure 2 illustrates the IVC architecture as implemented in Silicon Graphics 320.
Figure 2: Silicon Graphics 320 Architecture
Figure 3 illustrates the IVC architecture as implemented in Silicon Graphics 540.
Figure 3: Silicon Graphics 540 Architecture
The IVC architecture of the visual workstations makes them ideally suited to the following tasks:
- Modeling
3D modeling is a computationally complex and data-intensive task. This is why other Windows NT
workstations have graphics accelerators to off-load the CPU. You need to move large amounts of data between
main memory and the graphics processor while maintaining immediate access to the data. The higher the
memory bandwidth, the faster you can move geometry commands and textures between memory and graphics.
- Visualization
Visualization requires a level of performance not obtainable on most PC-architecture-based systems because
of the limitations in memory capacity, pixel fill performance, and I/O performance.
- Image manipulation
Image editing and exploitation require the same access to graphics processing. The larger the memory pool,
the larger the image with which you can work.
- Video editing
PCs are not very good at handling the bandwidth that video demands. This is why the only way you can work
with professional-level video on most Windows NT systems is by using a plug-in board that never integrates
video with system memory or graphics. Our I/O engine handles all the bandwidth of two uncompressed
streams of NTSC or PAL video without taxing the rest of the system. It also allows you to use video as a
graphics component; for example, video processing and the ability to treat video as a texture on geometry.
- Analysis
Analysis is a CPU-hungry task. Current PC workstation architectures support dual processors. Our systems
combine quad-capable processors (Silicon Graphics 540 only) and high-speed graphics acceleration. This
allows you to switch between changing a model to running an analysis and back all within a single machine.
We built an architecture that takes all this into account. The combination of the graphics subsystem, the high-bandwidth large-capacity
RAM, and the high-quality display engine supports graphics tasks from wire-frame 3D
modeling and fully textured real-time simulations to gigabyte image and professional video editing.
Feature Summary and Analysis
Silicon Graphics 320 is the price/performance leader, combining the 2D, 3D, imaging, and I/O capabilities with
integrated software solutions and an advanced display technology. Silicon Graphics 540 is the performance and
scalability leader, combining quad-capable processing with mainstream compatibility and economy. While Silicon Graphics 320 and Silicon Graphics 540 use the same Cobalt chipset, the primary differences between the two
systems are CPU capacity, memory capacity, number of PCI slots, and a real-time digital video (quad-stream
capable) option.
Shared Features
The SGI family of visual workstations integrates baseline workstation functionality rather than relying
on third-party add-in cards. The embedded functionality covers, but is not limited to, the following functions:
- Graphics
The graphics acceleration built into these systems is among the most powerful that SGI has ever
released on the desktop. This includes geometry acceleration, hardware-based texture mapping, dynamically
allocated texture RAM, and 2D image acceleration. The high-bandwidth graphics-to-memory bus allows you
to work with much larger models with greater realism.
The visual workstations include the following graphics features:
- Accelerated OpenGL
- Fast 2D and 3D geometry
- Texturing and shading
- Multiple light sources
- Highlighting the quality of lines
- Transparency
- Support for 1920x1200
- Rapid 2D and 3D manipulation without color distortion
- Reflection mapping
- Imaging
These systems have the bandwidth and memory capacities to let you load, pan, zoom, view, and edit large
images such as detailed photographs and maps at interactive speeds.
- Video
Both systems can sustain two streams of uncompressed NTSC or PAL resolution video, and both enable
multistream compositing and real-time playback. Analog video I/O is also built into both systems.
- I/O
Getting data in and out of the system is just as important as moving it around inside. That's why our I/O
systems have dedicated connections to the chipset for maximum performance.
The visual workstations include the following I/O features:
- 10/100 Fast Ethernet connector
- Two IEEE 1394 connectors
- Two USB connectors
- Serial port
- Parallel port
- Ultra ATA or Ultra2 SCSI
- Floppy and 32X CD-ROM drives
- Connectivity, interoperability, and application-migration tools
The SGI family of Windows NT visual workstations is optimized for all Windows NT-based
applications, including leading development applications like Microsoft® Visual Studio IDE,
Visual C++, Visual Basic, Visual J++, CASE tools, Symantec Visual Cafe9, JavaTM/Internet programming,
Vtune, and Mainsoft MainWin.
These standard offerings include Hummingbird NFS Maestro Solo and MKS file manipulation commands.
Also offered on CD-ROM with every system are "try-before-you-buy" applications such as Datafocus
NuTCRACKER 4.0 X/SDK and MKS toolkit.
Feature Comparisons
Table 1 compares the CPU, disk, and memory specifications for the visual workstations.
Component |
Silicon Graphics 320 |
Silicon Graphics 540 |
Processors |
Up to two of the following (must be matched):
- 350 MHz Pentium II
- 400 MHz Pentium II
- 450 MHz Pentium II
|
Up to four of the following (must be matched):
- 400 MHz Pentium II Xeon (512KB or 1MB secondary cache)
- 450 MHz Pentium II Xeon (512KB, 1MB, or 2MB secondary cache)
|
Hard drives |
- 6GB Ultra ATA (5.4K RPM)
- 10GB Ultra ATA (7.2K RPM)
- 14GB Ultra ATA (7.2K RPM)
- 9GB Ultra 2 SCSI (7.2K RPM)
(requires internal SCSI upgrade)
|
- 9GB Ultra 2 SCSI (7.2K RPM)
- 9GB Ultra 2 SCSI (10K RPM)
- 18GB Ultra 2 SCSI (10K RPM)
|
Memory |
- 128MB x 1 bank = 128MB (minimum)
- 256MB x 2 banks = 512MB
- 512MB x 2 banks = 1GB (maximum)
|
- 128MB x 1 bank = 128MB (minimum)
- 256MB x 4 banks = 1GB
- 512MB x 4 banks = 2GB (maximum)
|
Table 1: CPU, Disk, and Memory Comparisons
The Pentium II Xeon is part of the Pentium II family and is based on the same architecture as the Pentium II.
However, the Pentium II Xeon is distinguished by the following capabilities:
- Larger secondary cache (1MB, 2MB)
- Faster cache RAM
The Xeon cache memory runs at the same speed as the core processor, whereas the Pentium II runs at half the
speed of the core. This will result in better application performance for the Xeon even at the same clock speed.
- Greater scalability
The Xeon processor can scale up to four processors. (Intel has a chipset that supports four processors, but it is
positioned for servers and does not support AGP.)
Table 2 compares attributes of the Pentium II and Pentium II Xeon processors.
Component |
Pentium II |
Pentium II Xeon |
Clock rate |
350 MHz, 400 MHz, 450 MHz |
400 MHz, 450 MHz |
Cache size |
- Primary: 16KB instruction set, 16KB data set
- Secondary: 512KB
|
- Primary: 16KB instruction set, 16KB data set
- Secondary: 512KB, 1MB, 2MB
|
Cache speed |
Half-speed cache |
Full-speed cache |
Scalability |
1-2 processors |
1-4 processors |
Table 2: Pentium II and Pentium II Xeon Comparisons
Notes on Table 2:
- You cannot mix and match Pentium II and Pentium II Xeon processors.
- You cannot mix and match processors with different clock rates.
- You cannot mix and match processors with different secondary cache sizes.
Table 3 lists the visual workstations' video features.
Feature |
Silicon Graphics 320 |
Silicon Graphics 540 |
Analog composite video S-video I/O standard |
Yes |
Yes |
Bandwidth supporting dual-stream uncompressed video |
Yes |
Yes |
Dual serial digital video I/O (uncompressed; two streams in, two out) (dVideo) |
No |
Yes (option) |
Eight-channel digital audio input and output (dAudio) |
Yes (option) |
Yes (option) |
Encode one stream and decode up to two simultaneous streams of video in real time (dComp) |
Yes (option) |
Yes (option) |
Table 3: Digital Media Feature Comparisons
Table 4 compares the expandability attributes of the visual workstations.
Component |
Silicon Graphics 320 |
Silicon Graphics 540 |
PCI expansion slots |
Two 64-bit buses:
- One half-length 32-bit PCI slot on bus zero
- Two full-length 64-bit PCI slots on bus one
|
Two 64-bit buses:
- Four full-length 64-bit PCI slots on bus zero
- Two full-length 64-bit PCI slots on bus one
|
Storage bays |
- Two internal 3.5" bays (one preinstalled, one available)
- One front-accessible bay with standard, third-height, floppy drive preinstalled
- One front-accessible bay,
5.25" CD drive preinstalled
- One front-accessible bay,
3.5" x 1.0" height for additional accessory
|
- Three internal 3.5" bays (one preinstalled, two available)
- One front-accessible bay with standard, third-height, floppy drive preinstalled
- One front-accessible bay,
5.25" CD drive preinstalled
- One front-accessible bay,
3.5" x 1.0" height for additional accessory
|
Table 4: Expandability Comparisons
Silicon Graphics 320 Developer Station
The Silicon Graphics 320 Developer Station
is a recommended configuration for application developers. Available as an option is the Graphics Software Development Kit (SDK), which enables you to take advantage of the extensions SGI has integrated into OpenGL to help optimize your Windows NT application. Additionally, by joining the
SGI Developer Program,
you will have access to SGI technical resources and updates to the Graphics SDK.
In addition to the Developer Station, the following configurations are available:
Graphics Software Development Kit
The Graphics Software Development Kit (Graphics SDK) enables you to take advantage of enhanced performance and image-quality features by using SGI OpenGL extensions and other coding techniques in your applications. Source code that leverages these extensions is binary compatible with other Windows NT, thus eliminating the hassle of maintaining multiple code bases for your application. Also, while our dedicated hardware graphics engine already accelerates standard OpenGL 1.1 applications, the OpenGL extensions add the following features to every SGI visual workstation:
- OpenGL 1.2-equivalent functionality
- Occlusion culling--for use with complex, occluded geometry
- Additional texture-related functionality
- Pixel format for video YCrCb
- Windows OpenGL (WGL) extensions for pbuffers
To help you program with OpenGL extensions, the Graphics SDK provides a suite of headers, libraries, demos, sample code, and descriptive documentation. The Graphics SDK also contains an OpenGL debugger and other development tools. It contains the complete installation of OpenGL OptimizerTM 1.2, an SGI graphics API for large-model visualization. OpenGL Optimizer 1.2 takes advantage of the occlusion-culling OpenGL extension in the SGI visual workstations.
You can obtain the Graphics SDK in three ways:
Digital Media Software Development Kit
SGI plans to make a Digital Media Software Development Kit available to developers later this spring. The SGI Digital Media Software Development Kit for Microsoft Windows NT provides an application
programming interface to the video I/O, video image conversion, and audio/video synchronization capabilities of SGI visual workstations.
The digital media programming interface has two purposes:
- To provide efficient, low-level access to audio/video features for application developers who wish to program directly to the high-performance digital media capabilities of the SGI platform
- To provide a common interface layer to the audio/video capabilities of the visual workstations
This layer also serves as a foundation layer used by SGI engineers to implement components of the various industry-standard digital media APIs: Video for Windows, DirectShow, and QuickTime for Windows. The libraries are intended only for those applications that require multistream data handling. The industry-standard APIs have been tuned to support uncompressed data rates, and we recommend these for their broad platform compatibility.
The Digital Media SDK is in a pre-release phase at this time and is expected to be generally available to developers by the end of Q2 1999. If you are interested in being considered for a pre-release copy, please send email to devprogram@sgi.com, providing as much technical detail as possible regarding how your application will use multistream video.
Supported Graphics and Media APIs
The visual workstations provide the best platform for critical applications by using APIs that are fully compatible
with Windows NT-certified applications. These industry-standard APIs include:
- OpenGL 1.1 plus SGI OpenGL extensions
- OpenGL Optimizer 1.2
- DirectX (Direct3D and DirectDraw)
- Fahrenheit (future)
- GDI
As major portions of the OpenGL graphics pipeline are implemented in the hardware chipset, the visual workstations
significantly accelerate applications written in OpenGL. You can further tune your applications by using OpenGL
extensions, allowing additional performance and image quality features to be activated when running on the visual
workstations.
Even though the visual workstations are highly differentiated systems, they're fully compatible with existing
Windows NT applications. As such, you do not need to port or recompile to take advantage of the built-in
acceleration in the system. Moreover, the visual workstations will accelerate all the available standard graphics APIs.
Applications using the available APIs will automatically run faster on the visual workstations. The systems will also
run the full complement of off-the-shelf productivity applications.
These systems also serve the needs of developers working with various digital media types. These systems are
unique in their ability to play full-screen uncompressed video through the existing digital media APIs. The visual
workstations accelerate the following digital media APIs:
- DirectX (DirectShow)
- Video for Windows
- QuickTime for Windows
OpenGL
OpenGL is a representation of a graphics hardware processing pipeline. SGI created OpenGL and
turned it over to an industry-standards body, which creates consistency while allowing room for innovation through
extensions. A part of Windows NT, Windows 9X, and all UNIX® platforms, OpenGL is increasingly
used to integrate video with graphics.
Ninety percent of key visual workstation applications are OpenGL API-based; examples include:
- Alias|WavefrontTM MayaTM
- PTC ProEngineer
- Kinetix 3D Studio Max R2
More information on OpenGL
OpenGL Optimizer
OpenGL Optimizer is a higher-level library that efficiently manages the interaction with and display of very large
visual databases (typically CAD assemblies). OpenGL Optimizer issues drawing commands to OpenGL. It is
becoming adopted by a number of CAD applications including Prosolvia, Euclid Quantum, and the like.
OpenGL Optimizer 1.2 uses the SGI OpenGL occlusion-culling extension for the visual workstations.
This technology will also be included in the Fahrenheit Large Model API.
More information on OpenGL Optimizer
Fahrenheit
Fahrenheit is a collaboration between SGI and Microsoft--with contributions from Intel and HP--that
will produce three graphics APIs:
- Fahrenheit Scene Graph (fall/winter 1999)
- Fahrenheit Large Model (fall/winter 1999)
- Fahrenheit Low Level (fall/winter 2000)
For more information on Fahrenheit, refer to the following Web pages:
Display Options
Monitors are not included with the system. High-quality 17-inch and 21-inch CRT displays are optionally available.
Both systems are compatible with industry-standard 15-pin VGA displays.
Silicon Graphics 1600SW Flat Panel Monitor
The Silicon Graphics 1600SW flat panel display is the recommended display option for the visual workstations (and
O2TM). Silicon Graphics 1600SW is a pure-digital, high-resolution monitor:
- Thin-film transistor (TFT) monitor
- 1600x1024 (SXGA-wide) resolution
- Unique SuperWideTM format
- Large 17.3-inch diagonal screen
- Open LDI digital interface
- Windows NT workstation interface card installed at the factory
- 24-bit color (no dithering)
- 120° wide viewing angle
- Contrast ratio 250:1 (five times better than CRT)
- Brightness 235 cd/m2 (three times better than CRT)
- 25 W power supply
- Only flat panel display with ColorLockTM, a built-in color calibration solution
- White balance adjustable
- Stable display (no degaussing as there are no phosphors)
- Precalibrated to a set characteristic at the panel manufacturing line
More information on the Silicon Graphics 1600SW Flat Panel Monitor
Expansion Card Options
SGI offers a variety of optional cards to expand and extend the capabilities of the visual workstations;
each card has drivers specifically designed to take advantage of the bandwidth the systems provide. Additionally, 3.3
V-compliant PCI cards (both 32 and 64 bit) with Windows NT drivers will work with these systems.
The Digital Media Production Suite contains a family of products designed to interface the visual workstations into
digital media environments. These optional products are described in the sections that follow.
dComp
The dComp is a dual-stream motion JPEG (M-JPEG) 64-bit PCI option board for Silicon Graphics 320 and Silicon Graphics 540. It supports two simultaneous streams of decode for multistream effects and one stream of encode. The
card also supports a lossless encode and decode mode to maintain absolute quality while saving disk space.
Serial Digital Video Interface Board (Silicon Graphics 540 Only)
Serial digital connections transfer video data as digital bits. Professionals working from high-quality sources such as
Digital BetaCAM and DVCPRO50 can maintain end-to-end digital video sources by using the SGI
serial digital option.
The dVideo serial digital video interface board (SDI) is an option card for Silicon Graphics 540 that will occupy the
proprietary AV slot on the motherboard with I/O connectors on the rear of the system. The SDI card provides a total
of four 10-bit, serial D1 channels (two in and two out) as well as a genlock circuit suitable for locking to analog
house sync. The SDI option card also supports GPI and GPO events for interoperability with external video devices.
dAudio
Digital audio is the standard for everything from playing CD audio discs to recording for professional musicians. The
digital audio card supports true 24-bit sampling, which gives audio editors professional-quality results for editing
audio for games, music, or video production.
The dAudio option board for Silicon Graphics 320 and Silicon Graphics 540 offers eight-channel digital audio I/O
via optical connectors, AES/EBU I/O--providing up to 10 simultaneous channels--and a sync input for an external
video signal. In addition, the card supports synchronization in accordance with SMPTE 272M to the on-board video
via an internal sync connector. Up to three dAudio PCI cards may be installed for sample-accurate synchronization of
up to 30 channels of 24-bit digital audio on both systems. One or more cards can be synchronized to the on-board
video clock, an external video input, or an external AES/EBU input.
Summary
The SGI visual workstations enable you to:
SGI plans to make its first customer shipments of the Silicon Graphics 320 visual workstation near the
end of Q1 1999. The Silicon Graphics 540 product will be delivered soon thereafter. At launch, the product will be
localized for English, German, French, and Japanese. Localization for Spanish, Portuguese, Italian, Dutch, and
Swedish is expected to be completed shortly thereafter. Simplified and traditional Chinese as well as Korean
localization should be available in the spring.
The
SGI Developer Program
offers support to Windows NT developers who use SGI technologies and products such as the new visual workstations.
In addition, the Developer Program offers the following benefits:
- Free entry-level offering for all developers worldwide
- Automatic eligibility for benefits to current IRIX program members
- Free online access to the Graphics SDK and its updates for registered members
- New Windows NT support programs
Additional Resources
Refer to the following resources for more information:
Acknowledgments
For contributing their time and expertise to the writing and review of this article, thanks go to Alan Commike, Thomas True,
Julie Yen Johnson, Callum Eastwood, Lynn Crilley, Rick McLeod, Allen Bourgoyne, John Schimpf, Brett Butterfield, Kevin Connors, Joe Chien,
Sean Safreed, Kelli Ambrosi, and Risa Jacobson.