Encyclopedia of Computer Science and Technology

graphics card 213Industrial CompetitivenessBy the 1980s strong competitive threats to the U.S. computerindustry (notably from Japan) and some governmentfunding began to go to helping the American industry coordinateits research. An example is SEMATECH, the semiconductormanufacturing research consortium. (DARPAalso played an important role in the development of VLSI[very large-scale integration] circuits.)Another effort of this era was the Strategic ComputingInitiative, which was also in part a response to Japanesedevelopments—their Fifth Generation Computer Program.SCI aimed to develop hardware and software for advancedartificial intelligence projects, starting with a militaryfocus, such as autonomous vehicles, voice-controlled “glasscockpit” aircraft interfaces, and expert systems for battlemanagement.Although there is always fluctuation and changing politicalpriorities, there is no reason to believe that governmentfunding will not continue to play a very important role incomputer-related research and development. There will alsocontinue to be debates over the uses to which governmentsput computing technology, particularly in the military,intelligence, and national security areas.Further ReadingDefense Advanced Research Projects Agency (DARPA). Availableonline. URL: http://www.arpa.mil/. Accessed September 22,2007.National Center for Supercomputing Applications (NCSA). Availableonline. URL: http://www.ncsa.uiuc.edu/. Accessed September22, 2007.National Research Council. Funding a Revolution: Government Supportfor Computing Research. Washington, D.C.: National AcademiesPress, 1999. Available online. URL: http://www.nap.edu/readingroom/books/far/contents.html. Accessed September22, 2007.National Science Foundation. “Exploring the Frontiers of Computing.”Available online. URL: http://www.nsf.gov/dir/index.jsp?org=CISE. Accessed September 22, 2007.Redmond, Kent C., and Thomas M. Smith. From Whirlwind toMITRE: The R&D Story of the SAGE Air Defense Computer.Cambridge, Mass.: MIT Press, 2000.Roland, Alex, and Philip Shiman. Strategic Computing: DARPA andthe Quest for Machine Intelligence, 1983–1993. Cambridge,Mass.: MIT Press, 2002.graphics cardPrior to the late 1970s, most computer applications (otherthan some scientific and experimental ones) did not usegraphics. However, the early microcomputer systems suchas the Apple II, Radio Shack TRS-80, and Commodore PETcould all display graphics, either on a monitor or (with theaid of a video modulator) on an ordinary TV set. Whileprimitive (low resolution; monochrome or just a handful ofcolors) this graphics capability allowed for a thriving marketin games and educational software.The earliest video displays for mainstream PCs providedbasic text display capabilities (such as the MDA, ormonochrome display adapter, with 25 lines of text up to80 characters per line) plus the ability to create graphicsby setting the color of individual pixels. The typical lowendgraphics card of the early 1980s was the CGA (ColorGraphics Adapter), which offered various modes such as320 by 200 pixels with four colors. Computers marketedfor professional use offered the EGA (Enhanced GraphicsAdapter), which could show 640 by 350 pixels at 16colors.The ultimate video display standard during the timeof IBM dominance was the VGA (Video Graphics Array),which offered a somewhat improved high resolution of 640by 480 pixels at 16 colors, with an alternative of a lower320 by 280 pixels but with 256 colors. Because of its use ofa color palette containing index values, the 256 colors canactually be drawn from a range of 262,144 possible choices.VGA also marked a break from earlier standards becausein order to accommodate such a range of colors it had toconvert digital information to analog signals to drive themonitor, rather than using the digital circuitry found inearlier monitors.Modern video cards can be loosely described as implementingSVGA (Super VGA), but there are no longer discretestandards. Typical display resolutions for desktop PCstoday are 1024 by 768 or 1280 by 1024 pixels. (Laptops traditionallyhave had a lower-resolution 800 by 600 display,but many are now comparable to desktop displays.) Therange of colors is vast, with up to 16,777,216 possible colorsstored as 32 bits per pixel.Storing 32 bits (4 bytes) for each of the pixels on a 1024by 768 screen requires more than 3 megabytes. However,this is just for static images. Games, simulations, and otherapplications use moving 3D graphics. Since a computerscreen actually has only two dimensions, mathematicalalgorithms must be used to transform the representationThe basic parts of a graphics card. The card is connected to theCPU by the bus (often a special bus called the AGP, or AcceleratedGraphics Port). Graphics data can be generated by the CPU andtransferred directly to the graphics card’s memory, but most cardstoday perform a lot of the graphics processing using the card’s ownon-board processor for sophisticated 3D, textures, shading, andother effects.