Graphics cards, performance, and benchmarks

By William E. Davis
Xi Graphics Inc.
Denver, Colo.

Edited by Paul Dvorak

Getting high-performance 3D graphics out of Windows and Unix-based computers requires top-notch video hardware and drivers. While drivers are critical elements in graphic systems, old, slow, or out-of-date graphics cards are not improved by new drivers. And it's no surprise that lowcost drivers can ruin the performance of good cards. But find the right mix, and the results can be impressive.

The good news is that there is abundant benchmark information from several sources that makes it easy to compare performance of drivers and cards on several systems, especially for cards that support a library of graphic operations called OpenGL.

When drivers are developed by a single card and chip manufacturer, look for benchmarks on their sites. You might also research the history of support provided by card-chip manufacturers. Not all support is the same.

Companies, such as Xi Graphics Inc., independently develop graphics-driver software for 2D and OpenGL 3D cards, and for various Unix-based computers equipped with graphic cards from over 20 different card manufacturers. These drivers use proprietary registerlevel information provided under nondisclosure agreements. This information is necessary to design high-performance drivers.

Benchmarks for graphics cards running on Windows with drivers from card manufacturers are available from several Web sites and SPEC, the industry-sponsored Standard Performance Evaluation Corp. It uses SPECviewperf 6.1.2 suites of 3D-graphic benchmark tests. It contains five suites to measure performance of computers, cards, and driver combinations in five different tasks, such as animation, mechanical design, and modeling. The SPEC Web site (www.specbench.org) describes each test in detail.

For 2D operations, look for Xlibbased X11perf benchmarks. It measures window management performance as well as traditional graphics operations.

Examining the graphic-driver capabilities of a variety of cards and operating systems helps determine which drivers get the most out of which cards. The accompanying table compares just two cards. More are found at www.xig.com. Here's a brief glossary of benchmarks and what they test.

Viewperf measures performance in frames per second. The Viewperf testing program was originally developed by IBM and written in C. Since then, SGI, the former Digital, and other SPECopc members have updated and modified it. SPECopc is now a project group within the Graphics Performance Characterization Group managing OpenGL benchmarks. Operating systems covered by the SPECopc group include OS/2, Unix, and Windows NT and 95. Viewperf provides view sets which are combinations of tests using specific applications to test OpenGL performance. Larger scores indicate greater speed or more frames per second.

Advanced Visualization Test, or AWadvs04, is a key measurement of 3D geometry. It measures shading and rendering of the most common operations performed by Alias Wavefront's Advanced Visualizer, a workstationbased 3D animation system for modeling, rendering, image composition, and video output.

DesignReview, or DRV-07, gauges 3D modeling. It measures the most common operations performed by Intergraph's DesignReview. The software models piping, equipment, and structural elements, such as I-beams, HVAC ducting, and electrical raceways in plants.

Data Explorer, or DX-06, measures data visualization. It displays a set of particle traces through a vector-flow field using IBM's Visualization Data Explorer program for scientific visualization and analysis.

Lightscape Visualization System, or Light-04, is used to test radiosity visualization. Radiosity simulates the light reflecting off surfaces and onto others, resulting in soft shadows. Light-04, based on Discreet Logic's Lightscape Visualization System, has several tests for lighting, smooth shading, blending, line antialiasing, Z-buffering, and texture mapping.

Mechanical CAD, or MedMCAD-01, models the performance of several medium scale MCAD applications such as Pro/E from PTC and SolidWorks from SolidWorks Corp.

Conceptual Design & Rendering System, or ProCDRS-03, tests the graphics of PTC's CDRS industrial design software.

X11perf, a server performance program, measures the time it takes to create and map windows when starting an application by mapping a preexisting set of windows onto the screen (to remove icons in an application or pop-up a menu). X11perf also measures graphics performance for scrolling and operations that maps bitmaps into pixels. The test gauges line-and-point drawings, solid and patterned rectangle fills, and monochrome-tocolor expansions.

Quake III, a widely played video game, can be run in benchmark mode to measure performance in frames-per-second. Quake III has become a standard performance point of reference.