EOC Summary

1. How can I determine whether I should upgrade my existing computer or buy a new one? To determine whether you need to upgrade or purchase a new system, you need to define your ideal system and what it can do. Then, you need to perform a system evaluation to assess the subsystems in your computer, including the CPU, memory, storage, video, audio, and ports. Last, you need to determine if it’s economically practical to upgrade or whether buying a new computer would be best.

2. What does the CPU do, and how can I evaluate its performance? Your computer’s CPU processes instructions, performs calculations, manages the flow of information through a computer system, and is responsible for processing the data you input into information. It is composed of two units: the arithmetic logic unit and the control unit. CPU speed is measured in megahertz or gigahertz, or millions or billions of machine cycles a second. A machine cycle is the process the CPU goes through to fetch, decode, execute, and store data. You can tell whether your CPU is limiting your system performance by watching how busy it is as you work on your computer. The percentage of time that your CPU is working is referred to as CPU usage, which you can determine by checking the Task Manager.

3. How does memory work in my computer, and how can I evaluate how much memory I need? RAM is your computer’s short-term memory. It remembers everything that the computer needs to process data into information. However, it is an example of volatile storage. When the power is off, the data stored in RAM is cleared out. The amount of RAM sitting on memory modules in your computer is your computer’s physical memory. The memory your OS uses is kernel memory. At a minimum, you need enough RAM to run the OS plus the software applications you’re using, plus a bit more to hold the data you will input.

4. What are the computer’s main storage devices, and how can I evaluate whether they match my needs? Storage devices for a typical computer system include a hard disk drive, flash drives, and CD/DVD drives. When you turn off your computer, the data stored in these devices is saved. These devices are referred to as nonvolatile storage devices. Hard drives have the largest storage capacity of any storage device and the fastest access time and data transfer rate of all nonvolatile storage options. Floppy disks have a storage capacity of 1.44 MB, and CDs and DVDs have capacities from 700 MB to 9.4 GB. Portable flash drives allow easy transfer of 8 GB or more of data from machine to machine. To determine the storage capacity your system needs, calculate the amount of storage your software needs to reside on your computer. To add more storage, or to provide more functionality for your system, you can install additional drives, either internally or externally.

5. What components affect the output of video on my computer, and how can I evaluate whether they match my needs? How video is displayed depends on two components: your video card and monitor. A video card translates binary data into the images you see. These cards include their own RAM (video memory) as well as ports that allow you to connect to video equipment. The amount of video memory you need depends on what you want to display on the monitor. If you only work in Microsoft Word and surf the Web, 16 MB is enough. More powerful cards allow you to play graphics-intense games and multimedia. Your monitor’s size, resolution, refresh rate, and dot pitch all affect how well the monitor performs. For a clearer, brighter image, buy a monitor with a high refresh rate and a low dot pitch.

6. What components affect the quality of sound on my computer, and how can I evaluate whether they match my needs? Your computer’s sound depends on your speakers and sound card. Two types of speakers ship with most computers: amplified speakers and unamplified speakers. If you’re listening to music, viewing DVDs, or playing games, you may want to have speakers with a subwoofer. Sound cards enable the computer to produce sounds. Users upgrade their sound cards to provide for 3-D sound, surround sound, and additional ports for audio equipment.

7. What are the ports available on desktop computers, and how can I determine what ports I need? A port is an interface through which external devices connect to the computer. Common ports include serial, parallel, universal serial bus (USB), FireWire, and Ethernet, whereas specialized ports include IrDA, Bluetooth, and MIDI. To evaluate your port connectivity, check the devices you’d like to connect to your computer and look for the type of port they require. If your system doesn’t have enough ports, you can add ports through expansion cards (which you install in your system unit) and expansion hubs (which connect to your system through a port).

8. How can I ensure the reliability of my system? Many computer users decide to buy a new system because they are experiencing problems with their computer. However, before you buy a new system because you think yours may be unreliable, make sure the problem is not one you can fix. Make sure you have installed any new software or hardware properly, check that you have enough RAM, run system utilities such as Disk Defragmenter and Disk Cleanup, clean out your Startup folder, remove unnecessary files from your system, and keep your software updated with patches. If you continue to have troubles with your system, reinstall or upgrade your OS, and, of course, seek technical assistance.