With so much computer equipment on the market, often it is difficult for schools, colleges and universities to make wise purchasing decisions. When equipped with the proper knowledge, however, the process can be easier and more cost effective.
Spot buying Many computer manufacturers follow a practice known as spot buying, whereby the computer company buys components on the spot market as they are needed. This often means that while the computers have the same parts, they can be manufactured by different companies, causing compatibility problems.
Tier One manufacturers assure consistency by manufacturing primary components to its specifications for the duration of the model's life. These manufacturers use name-brand components of known quality and reputation, and have in-house or warranty service-provider networks.
Key computer components Computers are made up of several different components, each playing an important part in computer performance. Subsystems such as the hard disk, video card, cache, bus and RAM can dramatically affect the system's performance. Among the important components to consider:
*Processor. The CPU (central processing unit) is the computer's brain. The larger the number, measured in megahertz (MHz), the faster the computer can think. A machine labeled 166 MHz provides enough speed to handle most educational or reference software.
*Hard drive. The hard drive (or hard-disk drive) is the computer's permanent storage space and can fill up fast. Choose the appropriate amount of hard-drive memory, after determining what program applications are needed. Start with no less than 1 GB, and consider buying 2GBs.
*Memory. When the processor is thinking, it pulls information it needs from the hard drive and puts it onto a temporary desktop called memory or RAM (random access memory). Most computers come with RAM in the following amounts: 4, 8, 16, 24, 32 and, in some cases, 64 megabits. Memory represents speed--the more there is, the faster the computer will go. All things being equal, choose more memory over the next grade of processor.
*Cache memory. Some manufacturers skip using cache memory to save on expenses and offer the computer at a lower price. This generally robs the computer of at least 20 to 30 percent of its performance potential. Pipeline burst cache of 256k is the minimum.
*Monitor. A 15-inch monitor with a .28-millimeter dot pitch is considered standard today, but 17-inch monitors are becoming popular. Keep in mind that different monitors will have the same resolutions (dots per inch) but different refresh rates. The higher the refresh rate at a given resolution, the better the image.
If the monitor will be used at a high resolution (1024 x 768), make sure it is non-interlaced. Interlaced displays flicker and can trigger headaches.
*Video card. Video cards come with their own memory, usually 1 or 2 MB. The more memory, the more colors and higher resolution that can be displayed. Most people use a standard 1 MB Super VGA graphics card.
*CD-ROM drive. The CD-ROM drive can store software programs, games and videos in addition to sound. The speed of the CD-ROM drive is described by the number of times faster it is than the first CD-ROM drives, 4X, 6X, 8X. Most drives today are 8X and are available in speeds up to 24X.
*Multimedia. Workstation computers should be equipped with multimedia capabilities. Make sure that these computers each have a sound card with speakers, sound blaster or the equivalent. Faster is better, with 300 characters per millisecond a minimum and 8,000 recommended.
*Expansion slots. A computer that provides space for expansion will have a longer life because it can be upgraded as technology advances.
Minimum requirements When shopping for a computer, these are the minimum specifications: *Pentium 166 MHz processor (200 MHz preferred). *1.2 GB hard disk (2 GB preferred). *32 MB RAM (64 MB preferred) upgradable to at least 128 MB. *265k pipeline burst cache. *PCI video w/2MB VRAM. *8X CD-ROM or better. *15-inch SVGA color monitor (17-inch preferred). *1.44 MB floppy disk drive. *101 enhanced keyboard. *16 bit audio adapter (sound-blaster compatible). *32 Bit Mwave audio adapter (sound-blaster compatible). *10/100BaseT ethernet adapter. *28.8 Kbps fax/data modem or better.