Answers to common questions:

1. What is RAM? "RAM" stands for "Random Access Memory." It is measured in megabytes, or MB's or "megs" for short. RAM is the memory location where the operating system does its work and where programs run after they have been read from the hard drive.
2. What's the difference between RAM and memory? There is no difference—they are one and the same. However, do not confuse RAM with the hard drive. RAM is where the OS (Operating System) does its work; the hard drive is where your computer stores programs and data files.
3. How does RAM work? When the computer is turned on, it immediately loads the OS (Operating System) from the Hard Drive into the RAM, allowing the OS to run. Likewise, when you select software to run, it is also loaded into RAM. If the computer doesn't have sufficient RAM to hold the OS and all of the programs you are running, the computer will "swap out" some data from RAM to the hard drive to free up RAM (see "What is a swap file?" below). When the data that was swapped out to the hard drive is needed again, the computer must free up more RAM by swapping something else out first. Because the hard disk is considerably slower than RAM, this process can slow down the machine. See the "Memory Considerations" section below for more information.
4. What is a swap file? A swap file is a special file the operating system uses that resides on the hard drive. Often, a program is too large to reside completely in RAM. When this happens, data that does not fit in RAM is stored in the swap file. Because it resides on the hard drive, swap files are slower to access than RAM and, when used frequently, reduce system performance. Also known as "thrashing," frequent swap file use can be identified by a sustained access to the hard drive.
5. What is cache? Cache is a form of fast RAM that stores frequently-used data and instructions. Level One cache is special memory built into the processor that serves as a buffer and hashing area for incoming instructions. Level Two cache is special memory that speeds up the processor's access to the RAM. When an application "asks" for information or instructions, the system looks in cache first because data can be retrieved more quickly from there than from the system RAM, and that increased speed improves system performance. The cache is "flushed" and refilled regularly with new information, depending on what the computer is doing. A machine these days needs at least 512k of cache to operate at peak efficiency. Often, one megabyte or more of Level Two cache is preferable for high-end systems.
6. What is the hard drive? The hard drive is the hardware that physically stores the operating system, all the software, and all your data. In the past, the hard drive was measured in Megabytes (MB or "megs"), while today's much larger hard drives are measured in Gigabytes (GB or "gigs"). In years to come, we can expect them to be measured in Terabytes.
7. What is an OS and what does it do? An OS, or Operating System, is the first program loaded when a computer is turned on. It tells the computer how to boot up, controls all the hardware in a computer, allows you to interact with the computer, and handles loading and running programs from the hard drive. Some examples of operating systems are DOS, Microsoft Windows 3.1/95/98/NT, MacOS, and UNIX. Some examples of software are Microsoft Word, Netscape Navigator, AOL, and Word Perfect. Some examples of hardware are hard drives, floppy diskette drives, CD-ROM drives, memory, sound cards, video display, keyboards, and mice.
8. What is processor speed? Processor speed is an indicator of the processor's raw power. The measurement is generally given in Megahertz (MHz), with the higher number indicating faster performance within a processor family. Modern processor families include Intel's Pentium, Pentium MMX, Pentium II, and Pentium Zeon, as well as Motorola's PowerPC 604e and G3. Each family of processors differ in terms of architecture. Keep in mind, however, that even the fastest processor can seem slow if there is not enough RAM in the machine to run without swapping. See "Memory Considerations" below for more info.
9. What is a NIC and what does it do? A NIC, or Network Interface Controller, is a piece of hardware that allows a computer to be connected to a network. One commonly used network type is Ethernet. An Ethernet jack looks like a regular telephone jack, only wider. You cannot use a regular telephone cord with an Ethernet jack; rather, you need a special station cable.

Hardware considerations

Before you can determine what kind of computer to buy, you must first determine how you intend to use it. For example, if you just need a machine to handle E-mail and general word processing, you should be less concerned with the processor speed and more concerned with RAM and hard drive size. If, in addition, you need to run statistics (e.g., SPSS-X, SAS, etc.), perform graphics editing or creation, or do any other processor-intensive task, you should also be concerned with the processor speed. The faster the processor, the better the performance.

Once you determine how you want to use the computer, investigate the software you want to run. Look at the software manufacturer's recommendations for RAM, hard drive size, and processor speed. Most software today is packaged on a CD, so make sure your machine has a CD-ROM.

Operating System considerations

When selecting the operating system you want, remember to check your software for compatibility. If you already own software written for an older OS, like MS-DOS or Windows 3.11, it may not run properly under Windows 95, Windows 98 or Windows NT 4.0. The same is true for the Macintosh OS.

Memory Considerations

As of late 1998, the general rule of thumb for memory is to have a minimum of 64MB RAM. Windows 95 uses the first 24MB of RAM, leaving the remaining 40MB to run your software. Windows NT 4.0 uses the first 31MB of RAM, leaving the remaining 33MB of ram for your software. Mac0S versions 7.5 and above generally use the first 8 to 16MB or RAM for the OS, depending on what extensions are loaded, leaving up to 56MB available to run your software. The more programs (e.g., software for E-mail, word processing, games, etc.) you run simultaneously, the faster you use the remaining RAM. Once the remaining RAM is exhausted, your computer begins swapping out to the hard drive, which can slow down the machine noticeably.

Custom-built machines from Gateway and Dell generally consider 128MB RAM standard on any machine above the Pentium II 300 series. Although it may be hard to imagine using 128MB RAM, remember that the newer software programs are loaded with options, and all those options eat up RAM. In general, you can expect newer releases of OS and software applications to continue to require more RAM than previous releases.

Software considerations

When selecting word processing software, you should consider compatibility with other brands of word processing software. The two most widely used word processing packages used on the USM campus are Corel WordPerfect and Microsoft Word. Microsoft Word will accept and convert documents written in WordPerfect or Microsoft Works. Of the computer labs on campus available to students, faculty and staff, most have the Microsoft Office 97 Professional package, which includes Microsoft Word. Corel Word Perfect is also installed in some of the labs.

Compatibility can become a major problem if one computer fails and you have to take your backup disk to another machine that doesn't have the exact same software or version of the software. Furthermore, word processing is not the only software that should be versatile. Look for compatibility in, for example, software like Microsoft Excel and Lotus 1-2-3, which produce spreadsheets.

As users gain experience, many look for compatibility between their word processing, spreadsheet, calendar, E-mail, and database software. Such integration allows the user to import and export data from one package to another. For example, you might create an address book in your calendar and use it to automatically grab E-mail addresses for your correspondents, as opposed to having to manually type the information. For another example, you may need to include a spreadsheet within a report you created in your word processing software. If you anticipate having such needs, you should consider purchasing a package deal that includes all of these features. One example of packaged software is Microsoft Office Professional 97, which includes Word 97 for word processing; Excel for spread sheets; Outlook for calendar, E-mail, and address books; Access for databases; and PowerPoint for slide presentations.

Where should I purchase my computer?

There are several options available for purchasing computers, and you should weigh each before making your final decision.

1. Prepackaged from a reputable dealer. You can select prepackaged computers "off the shelf" from dealers such as Office Depot and Campo. Dealers generally offer several makes and models from different manufacturers. On the positive side, you can often find bargains as newer models replace older models, and you can take your computer home the day you make your selection. On the negative side, seldom will you find a machine that fits your needs exactly. The most common problem is lack of adequate memory and lack of a NIC. To upgrade a prepackaged machine, you must send in the warranty card, then notify the manufacturer's customer service department and follow their guidelines to make upgrades. If you allow an unauthorized dealer to modify or upgrade the system, you generally forfeit the warranty on the system.
2. Custom ordered from reputable dealer. You can have the computer of your dreams built to your specifications by such companies as Dell and Gateway. On the positive side, you get exactly what you want, from hardware to software to operating system. On the negative side, you must be willing to wait awhile to receive your new computer. Cost is usually comparable to off-the-shelf prices, however, and a full range of configurations is available.
3. Custom built from local dealer. You can have a machine built by a local company to your specifications. On the negative side, you forfeit some degree of knowledge about the internal makeup of the machine—you may never really know what brand parts or configuration the local dealer installs in the machine. Furthermore, if the company goes out of business, you have no warranty whatsoever. On the positive side, such local dealers can provide a high level of personalized service—there's someone "in town" who knows your machine.
4. Mail ordered. You can mail order computers in either the prepackaged format or the custom built. The same rules from options one and two above apply here.

When selecting from whom and how you purchase your computer, consider foremost your own personal comfort zone. Which option gives you the greatest feeling of security? Obviously, what's right for one person may not be right for another.