CS 150 Computer Literacy

Parts of a computer / Buying a Computer

                                             
                                             

 

These are terms you'll see in advertisements and hear from sales people
  • Minitower vs Desktop - basically the same. The Desktop lays flat and the Minitower stands upright. The Minitower has a little bit more room available for upgrades or add-ons. Consider desk space when deciding which one to purchase.
  • Laptop vs Desktop - A laptop (or notebook) comes in smaller, portable sizes. They are more expensive and have lesser hardware for the same size as a desktop
  • Mhz(Megahertz) - Ghz(Gigahertz) - microprocessor speed. The faster the better, of course. This works conjointly with the amount of RAM your computer has to determine how fast you can process data and the response time you'll experience on your computer.
    • A processor having a speed of 800mhz can do approximately 800 million instructions per second.
    • Front side buss - the greater - the faster
  • Microprocessor(also known as processor or CPU) - This is the chip used for the "brains of the computer." If you've watched TV or read any magazines in the last five years, chances are you've seen the advertisement "Intel Inside." Intel Corp dominates the market for microprocessor chips although their competition makes some pretty good chips. AMD is the biggest competitor of Intel right now, and they are gaining ground with a very good processor for much less money.
      (3.6 Gigahertz is the top speed I've seen, five years ago it was around 66mhz so in five years it's gone from 66mhz to approximately 3600mhz) Moore's law
  • CPU stands for Central Processing Unit, but there are a lot of computers today that have more than one processor (duel processors), so the acronym CPU is starting to be phased out.
  • Memory
    • RAM size expressed in terms of megabytes (MB). 128 is the minimum you need to use software available today. If possible, go for 256 megabytes (or even better 512MB) so that you won't need to upgrade it in a short time. This is the amount of memory that applications use to operate and where data is temporarily stored until you permanently save it to a disk. Even though the processor speed is important you can gain a lot of speed and performance by increasing the amount of RAM. The mininum amount of RAM I would have on a computer for my work would be 256 Megs
      • Notice Amounts of RAM usually doubles for each step: 8 MB, 16MB, 32MB, 64MB, 128MB, 256MB, 512MB, 1024MB.
    • Cache memory is expressed in kilobytes. 256 kilobytes is standard although 512 kilobytes are available, I recently saw a motherboard that had 1MB of Cache memory. This is an interim memory that stands between the CPU and RAM. It allows your computer to execute commands faster than if it had to go to RAM to collect the command each time. L1 Cache memory is actually built into your microprocessor chip itself while L2 Cache memory is found on the motherboard.
    • Flash memory is usually found in portable computers, but it's also found in more and more embedded systems and PC's. It takes the place of RAM. It is non-volatile memory that can be erased electronically and reprogrammed. There is a also a flash ROM you see sometimes these days. I have flash memory cards for my Palm and my Webpad, I'll bring them to class.

     

  • Hard Disk Drive size is expressed in terms of  gigabytes. A 20 to 80 Gigabyte hard drive is pretty much the standard today. You may not think you'll ever use that much but you will. Why? Mostly because software programs are becoming larger and larger. If possible, get as much hard drive storage as you can afford. The speed of harddrives are expressed in RPM (revoloutions per minute) 5400, 7200 and 10,000RPM's are the three most frequently found.

 

  • CD-ROM speed is expressed in terms of 8X, 32X, 40X, 56X etc. This term refers to the speed at which your computer transfers or reads data from the Compact Disk. The measurement is based on how much faster the particular version is as opposed to the very first CD-ROM ever built. If you intend to use a lot of special effects (graphics, sound, motion, etc) you'll want to get a higher speed CD-ROM player. You will want a CD-ROM player though because most software programs are only available on a Compact Disk.
  • DVD stands for digital video disc players. This newest technology was introduced to the market in March 1997. The device is intended to eventually replace the CD player although, in my opinion. Do you need one right now?  They are available up to 10X speeds.
  • Audio speakers: the basic speakers that come with most systems are adequate if you don't intend to use lots of special effects or use programs that rely on sound performance. Most sound cards are measured in bits with 16 bits being the normal. If you want very good sound try to go with 3D Surround Sound and high quality speakers.
  • Fax modem speed is expressed in terms of bits per second. This term refers to the amount of data that can be transmitted over the modem. 56 kilobytes per second is the standard.  Remember though that data transmission speed also relies on the available transmission lines (usually telephone cables) and on the size modem that is available on the computer to which you are trying to connect.
  • NIC (Network Interface Card) allows connection to a network, it's an expansion card. Most high speed Internet access, such as DSL lines need a NIC (usually Ethernet) instead of a Modem. Most computers today are coming with a NIC card, and if it's not included you can add one for a $20-$30 usually. You have to have one of these to use Resnet in the dorms
  • Expansion slots refer to the areas in which you can add peripheral devices or special add-ons. Most computer systems have a minimum of 5 expansion slots available. Expansion slots are inside the computer connected to the motherboard. Expansion Cards, like a modem are connected to the slots.
  • Video Cards - have memory from 16MB to 256 MB. If you're a gamer - go big! otherwise a standard built in card is good.
  • Sound Cards - can also be built in or seperate. If you listen to music over your computer or are producing videos, then you might consider upgrading.
  • Expansion Bays - these refer to the openings in the front of your computer that things like DVD and CDROMS go in.
  • Ports come in two kinds, both of which are standard items. The serial port is the one to which you'll attach your keyboard and mouse. The parallel port is the one to which you attach your printer or other high data peripheral devices such as scanners.
  • USB (Universal Serial Bus) - These are listed in several computer listings and they are a very usefull tool. USB ports, by definition, are a port that can connect up to 127 different peripheral devices with a single connector. It can eliminate the need to install expansion cards into expansion slots (need to know what expansion cards are on the test too). USB devices are connected to each other outside the system and then a single cable attaches to the USB port. Scanners and many digital type cameras are not connecting to your computer via a USB port.
  • Firewire higher speed than usb
  • Infrared

Peripheral Devices

  • Monitors: believe it or not, the monitor is not always included in the basic purchase price. Read the fine print of those advertisements before you're swept off your feet!
    • CRT
    • flat screen
    • LCD
    • flat panel
    • plasma
  • These days the monitor can be the most expensive thing when buying a new computer. But spending the money can also be worth it, bigger the more expensive. You don't need one as big as the screen in EPS103 but a jump from 17" to 19" can make a big difference.
    • Interlaced vs Noninterlaced - a non-interlaced monitor will process picture changes faster than will an interlaced monitor.
    • Refresh rate refers to the speed at which your picture changes will process. The faster the better.
    • Resolution refers to the depth and breadth at which your monitor will display a picture. 640 by 480 is the minimum. If you choose a monitor with a higher resolution such as 1280 by 1040, your picture will be brighter and crisper. Consider the higher resolution if you intend to use a lot of graphic data.
    • Size is measured in the diameter of the screen. 15" is standard while 17" and 20" are very good for viewing graphics and large data screens.
  • Printers
    • dot matrix - rather slow and not very good for printing graphics or colors.
    • bubble jet - will produce good quality print similar to a laser printer.
    • inkjet - about the same as a bubble jet printer
    • laser - the best you can buy for high quality output.

When you're selecting a printer you should consider the cost of printing not just cost of printer. Compare the prices of the ink cartridges both color and black ink. Does the printer require special paper or can you use standard bond paper. In the long run these considerations will determine the cost of printing.

Software

You should determine which software programs you think you may want before you select your hardware. Lots of people choose their hardware first only to find out too late that the software that they want is too large for the hardware components. Almost every PC comes with Windows XP and usually has Microsoft Works pre-loaded. You'll also find that most PCs have other software programs already installed on them such as games and learn-to-type programs.

When you're purchasing software programs for word-processing, spreadsheets, and database programs you have several different methods of selecting what you want. Deciding what all you want to do should decide the type of programs you purchase. If you think you'll only do word-processing and not spreadsheet or database work then just purchase a word-processing program such as Microsoft Word or Corel WordPerfect.

If, however, you think you'll have a need for all three types of programs you may save money and make your work easier and more efficient by purchasing a suite of programs. The suite contains the same software that you can purchase separately but it is easier to load the suite onto your computer and it's easier to transfer data between the programs. And, it's usually cheaper to purchase a suite than to purchase the individual programs. Two good suites are Microsoft Office 2002 and Corel WordPerfect Suite.

A word about Microsoft Works: This program usually comes pre-installed on most PCs. It includes a word processing program, a spreadsheet program, and a database program. These programs are pretty good but just don't have as many fancy commands and operations as Microsoft Office or Corel WordPerfect Suite Seven. Unless you intend to do a lot of heavy office work, Microsoft Works will probably suffice for you as an average home user. It just doesn't work for this class.

Windows XP is designed for the home user

Windows XP Pro has additional features for networking and system administartion with large groups of computers. You probably don't need XP Pro if you only use your computer at home.

Upgrade or purchase a new system?

Many of us already have a computer. It may be one year old or five years old. If you're in this situation you may wonder whether it's better to upgrade or just purchase a whole new system. "Penz on the situation," as the saying goes. The rule of thumb is that if your current computer is more than a year old you should purchase a new one. If it's less than a year or two  old, you need to consider the cost of all the upgrades that you want to do. If you simply want to add more RAM, it's probably better to do just that. It'll cost you $100 or less. If you want to add a new processor, more RAM, a sound card, etc, it's probably cheaper in the long run to purchase a new system. The more capacity you want to add, the harder and more expensive it is to integrate your old system with the new technology. Some older technology simply cannot be integrated with the new technology. Or is that newer technology can't be integrated with the older technology? ;-)

Tips for purchasing computers

Just a few quick tips about purchasing a computer -

  • NO FEAR - approach this purchase with the same common sense you'd use for any other purchase.
  • Decide what are you going to use the computer for and then base your purchase on that.
  • Base your buying decision on your needs not your neighbor's. Everybody I know swears their system is the only one worth spending money on.
  • Price is important, don't fool yourself. Make sure you understand what the price covers. For instance, lots of low priced computers don't include a monitor.
  • Understand the hidden costs associated with purchasing a computer that eventually show up on your credit card anyway. You're going to need basic items such as extension cords, surge protectors, diskettes, additional software programs, maybe a new desk, etc. Factor these items into your decision.
  • Which one is better: local retailer vs mail order. That depends on your personal situation. If you think you'll need technical support or follow-on help, then you may be better off with a local retailer. If you are more concerned about price, go with a mail order house. Try these Web sites if you're interested in purchasing a computer system or parts from mail order:
 

Dell

HP

Gateway

New Egg

Tiger Direct
 

You can also purchase many different software programs on the Web. You can either have the software sent to you in the traditional manner or download it right off the Web. Rather than list for you the hundreds of different places to get software, use one of the search engines to browse the Web for the software you're interested in. The bookstore offers a lot of different software at student prices.

Murphy's Law of Buying Computers

Whatever you buy today will be obsolete tomorrow

Whatever you buy, your neighbor will have something better

Whatever you buy, the price will be lower in a month

Whatever you buy, you'll wish you'd bought something else

Bottom line - buy it and enjoy it (don't look back)

Purchasing a Computer

If you're in the market for a new computer then you should use this checklist for your comparison shopping.
 
Basic Considerations
TR
Item Desired Merchant 
#1
Merchant 
#2
Merchant 
#3
Processor 3.0 GHz
RAM size 128 MB minimum 
256 Mb
512 Mb
Harddrive Size 20.0 GB mininum
40.0 Gb
80.0 Gb
Monitors15" min
17"
19"
Printer Included??
Other Included??
Other considerations
. . Merchant #1 Merchant #2 Merchant #3
Surge Protector . . . .
Do you have an available phone jack for modem . . . .
Shipping (optional) . . . .
Desk space . . . .
Removable Disks . . . .
Specific software . . . .