PC Users Guide: General Computer Information

Personal Computer tips for new user. Advice on equipmet, upgrages, memory. Introduction to terms and problems.

Introduction

In the office and the home, computer networking seems to be moving the way television sets and microwave ovens did many years ago. A recent survey conducted by a leading IT magazine in South Africa revealed that 92 % of the sample owned at least one computer at home, 78 % had internet access and nearly 30 % are networked. This may seem a small number of networks in the home, but this number is growing rapidly.

Networking need not benefit only large corporations, the home user can find that networking has endless possibilities, from sharing printers to Internet access and software. Before we look at networking, we need to look inside the computer and become familiar with crucial components that make your computer functional.

Once the computer user becomes familiar with the basics of their computer, they can confidently troubleshoot and repair minor glitches and eventually set up their own network in their home.

Overview of the Computer Case and its Contents

The case contains the essentials of the computer. It offers vital protection and cooling while providing an organised layout for the components. Let's take a look at some of the parts inside this case.

The System Board

The system board is where the processor, cache, video card and other devices would plug into. We will look at each of these at a later stage, but first we will delve into the brain of the system board; the Chip set. The chipset and the system board control the processor's access to memory and the flow of data to and from devices. The chipset also determines certain features the PC can support. These features include the type of processor, memory and system bus you can use in your PC.

The System Bus

The system Bus consists of electrical channels through which the various parts of the computer communicate. You can easily recognise the bus. The are sets of slots that cards plug into. A video Card would receive information from the processor through the system bus. The processor then saves this data onto the hard drive.

A very important aspect of the bus is its architecture. This will greatly impact on the performance of the computer and will affect the choice of video card and other devices.

Power

It may seem pointless to mention, but power if obviously an important consideration in any computer. The power supply can be found inside the casing. The power supply is always situated in a position to allow for the connection of the external power leads. The external power supply is transformed into four DC voltages that the PC can use. The four DC volages are +5, -5, +12 and

The Motherboard

First we will take a brief look at the heart of every system; the motherboard. This is the heart and brain of every computer, whether it is a Mac or IBM Compatible.

A motherboard is the large printed circuit board in your computer. It serves as the backbone of the computer. Peripheral hardware (add- ons i.e. printers, keyboard, mouse, etc"¦) is connected to the motherboard. The motherboard contains the Central Processing Unit, known as the CPU. All your memory is held here along with interrupts, addresses, ports, and DMA Channels and the data bus. These we will discuss in detail in the following series. These terms may seem a little daunted right now, but they will soon become familiar to you.

First and most important is the CPU. This is the BRAIN of the computer. We have all heard of the INTEL Processor. These processors range from 8086 & 8088 (earlier types) to the latest PENTIUM PRO, PENTIUM I, II & III and more recently, the 1 GHz. The computer uses these processors perform/run programmes.

Other processors are AMD and Cyrix. AMD has taken INTEL on in a big way lately. These processors offer the same performance at a better price, but are not 100% compatible with all software and devices.

When choosing the right processor for your home system, you need to consider what it is the computer's main function. You may looking for an home/office computer for running the household accounts and writing documents, the kids want something to run the latest multimedia game, and mom wants to retouch old photographs. The basic rule of thumb is that the AMD processors are mainly suited for high-end graphics and multimedia, great for games. The INTEL is for general computer use. Remember though, that using programs like Adobe Photo Shop and other image edited programs, you will need a very large hard drive with lots of RAM. These programs use up a great deal of memory. We will look at memory a little later.

In order to execute a program, the CPU must be able to quickly perform various functions like Reading and writing information into the computers memory and recognising commands, which it carries out, directing the operation of other parts of the computer.

Speed is a crucial factor with all CPU's. The CPU's speed is measured in terms of MEGAHERTZ (MHz). 1MHz = 1,000,000 cycles per second. The typical speeds range from 16MHz (older machines) to 300 MHz and more recently 1 GHz (gega hertz). These speeds are called CLOCK SPEEDS. An internal timing clock controls the speed. Some instructions can take more than one clock cycle to complete. Therefore; the actual work a processor can perform is measured in MIPS (Millions of Instructions Per Second)



To the end user, the most noticeable difference between the different processors is the speed at which the computer performs tasks.

Table 1.1 represents the different speeds of the INTEL CPU's. Measured in MIPS

8086 0.33

8088 0.33

80286 3.00

80386 11.00

80486 41.00

Pentium I Over 100

Pentium II & the Pentium Pro Over 300

Newer and faster processors are being developed at an alarming rate. Electronic technology is growing so fast that the latest processors will become old news within a year. Not all computers need the latest processor. Most applications can run on the earlier types, but there are people who try to do the impossible and run Windows using a 386 (old, very old). It may work but you can go make a martini while waiting for you command/ request to be executed. Windows 95, Windows NT , and later versions demand a lot of system resources. A 386 with 4MB of RAM simply will not do. Unless you want to go have a beer at the pub while waiting for your computer to wake-up.

Bits and Bytes

We are not talking about cocktail snacks!

All the information travelling across the motherboard is represented digitally (0 or 1). These ones and zeros are referred to as BINARY NUMBERS.

Try this:

Go to your start menu. Chose PROGRAMS, then ACCESSORY, and open your CALCULATOR.

Type this number in: 10

Then click on BIN on the left hand side of the calculator. You will see the number 10 change to 1010 . This is BINARY.

The number 1010 represents 10 in binary. 10 is a decimal number.

Letters and numbers all have a binary equivalent.

The 1's and 0's (binary digits) are simply called BITS. When a computer processes 1's and 0's, however, it does so in BYTES, which are groups of 8 bits. The typical computer today has over 8 million bytes of memory, we use a more simple form of metric terms to describe quantities of memory storage:

A BYTE = 8 BITS

A KILOBYTE = 1024 BYTES

A MEGABYTE = 1,048,576 BYTES

A GIGABYTE = 1,073,741,824 BYTES.

You don't have to remember the actual figures, only that one gigabyte can handle a lot more memory than a megabyte A Kilobyte byte can handle less and so on until you get to the baby; one bit. When you see that a computer has 16 MB; then you know it can handle 16 Megabytes of memory before it tells you to fog off.

Bits and Bytes are also a very important consideration in networking. The number of bits per second travelling across a network can seriously affect the performance of your network. This applies to the largest of all networks; the Internet.

RAM and ROM

ROM stands for Read-Only-Access and RAM stands for Random-Access-Memory. The microprocessor can read and write information to and from the RAM during operation. The most significant difference between RAM and ROM is that RAM looses all its information when the computer looses power. In a computer the ROM is referred to as the BIOS (Basic-Input/Output System). When a machine is first started up, the microprocessor first looks for the BIOS. The BIOS runs some standard tests. These tests are called the POST (power up self-test).

Next, the BIOS goes to fetch the BOOT SECTOR. The boot sector is then stored in the RAM after it is read off the hard drive. With the boot sector safely stored in the RAM, the microprocessor can now begin executing the boot sector's instructions from there. Ultimately from here the operating system is loaded and executed. This must all happen before you are able to operate your computer. Amazing isn't it?

The Hard Drive

Before we begin looking at how to set up a simple network, there are just a few more very important components to look at. The computer is made up on many different components and each can have a whole chapter dedicated to them. But we are only going to look at the most important for now. The next crucial component of any computer is the hard drive, also sometimes referred to as the hard disk.

Hard Disks have an important function, they store changing digital information in a relatively permanent form, making it possible for the computer to retain information even when the power is off. This information can be easily retrieved from the hard drive. Hard disks use a magnetic recording technique that can be easily erased and rewritten. A typical computer will have a hard disk with the capacity to store up to 8 gigabytes of information. This information is stored on the hard drive in files. A file is a collection of bytes. When a program is executed, the computer sends a request to the hard drive to retrieve the bytes. These bytes are then sent to the CPU one at a time.

The number of bytes per second the hard drive can deliver to the CPU can be a measure of the performance of your hard drive. A rate between 5 and 40 megabytes per second can be considered the norm. Another way to measure the hard drive's performance would be to look at how long it takes for the CPU to receive the first byte of data after it has requested the file. 10 to 20 milliseconds are common. Remember to always look at the capacity of the hard drive when you decide to upgrade. It will mean the difference between functional and frustrating.

An important consideration when buying new components for your computer is compatibility. Always check the Hardware Compatibly List supplied with your hardware and software before going to the store. Mistakes can prove costly.

© High Speed Ventures 2011