Tuesday, August 3, 2010

External hardware components and peripherals, cost, image and function

Monitor: This is used to display output created from the use of various computer programs.
Dell S2409W 24" Widescreen Flat Panel Monitor
$499

Keyboard: Controls the operation of a computer, as well as allowing a user to type letters and numbers.
Shintaro Wireless Media Center Keyboard
$74.80


Mouse: a hand-operated electronic device that controls the coordinates of a cursor on your computer screen as you move it around on a pad.
Logitech® NX50 Corsica Laser Mouse
$49.50


Printer: An output device attached to your computer that produces printed copies on paper (hard copies).
Lexmark E120n Mono Laser Printer
$376.20


Modem: Allows the user to connect to the internet.
NetGear DG834N ADSL Modem
$146.81

Sunday, August 1, 2010

A Description of the different PC and Macintosh Operating Systems

Although computer families such as IBM PC-compatible and Macintosh can be distinguished on the basis of CPU type, it is mainly their choice of operating systems which gives them their particular identity. Microsoft dominates the market , with over 90% of all computer systems using one of the Windows operating systems - Windows XP, Windows Vista. Even some systems using Microsoft's original Ms-DOS can still be found.


On the other hand, Macintosh computers use Apple's Macintosh Operating system (MAC OS).

To appreciate the differences between Windows and Mac OS, while Apple did not invent the graphical user interface, they were first to make a fully realised, commercially viable product. Microsoft produced their own graphical user interface - Windows.

The Relationship between an Application program, the operating system and hardware

Computer Hardware consists of the physical components that make up a computer. Some examples are and Microprocessor, a Hard Drive, or a Motherboard.


Computer Software consists of applications or programs that the user runs on a computer, such as a word processor or a video game.

An Operating System is a specific piece of software that allows other software to manipulate computer hardware to achieve a desired effect. Some Operating Systems are Microsoft Windows, Unix/Linux, or Apple OS

Basically the three interact as follows:

Hardware <-> Operating System <-> Software
(<-> specifies an interaction between two components.)

In addition computer hardware deal with different devices that interact into the computer software then it show the capacity and data of the applications while the operating system it is the combination of performance which spreadout to access each other components.

A Description of the Boot Process

The Boot process is the process which starts up the computer system, starting the computer's operating system and identifying its hardware and software components that all work together.


In order for a computer to successfully boot, its BIOS(Basic Input Output Operating System), operating system and hardware components must all be working properly; failure of any of these elements will result in a failed boot sequence.
When computer's power is turned on, the CPU initializes itself, which is triggered by a series of clock ticks generated by the system clock. Then the initialization looks inot the system's ROM BIOS for its first instruction in the startup program. The ROM BIOS stores the first instruction which then in turn runs pwer-on self test(POST), in a predetermined memory address.

POST checks BIOS chip and then tests CMOS RAM. If there is no battery failure detected during POST, then CPU is initialized followed by checking hardware devices, secondary storage devices such as hard drives, floppy drives, ports, keyboard and mouse to ensure they are functioning properly. Once the POST has determined that all components are functioning properly and the CPU has successfully initialized, the BIOS looks for an operating system to load

The order of drives that the CMOS looks in order to locate OS is called Boot Sequence.

The Functions of a Computer Operating System

The operating system is the core software component of your computer. It performs many functions and is, in very basic terms, an interface between your computer and the outside world. In the section about hardware, a computer is described as consisting of several component parts including your monitor, keyboard, mouse, and other parts. The operating system provides an interface to these parts using what is referred to as "drivers". This is why sometimes when you install a new printer or other piece of hardware, your system will ask you to install more software called a driver.
Among the main basic functions, every computer operating system does include the following:
  • Managing Random Access Memory (RAM)
  • Managing computer hard disk
  • Scheduling various tasks on computer
  • Providing reasonable level of security to computer to prevent any extrnal party to gain access to your computer.
  • To navigate various programs on computer ant many more

The Environment Considerations in the Disposal of Computer Hardware and OH+S considerations in the use of computer equipment.

A) Environmental Considerations in the disposal of computer system.

There is large Carbon footprint in IT production industry but that can be reduced by re-use and re-deployment of redundant IT equipments known as Computer Recycling.

Most of the environmental concerns with computers lie with the monitor, specifically its catode ray tube (CRT). On average, each color monitor contains 4 to 5 pounds of lead, considered hazardous waste when disposed of.

There are other hazardous materials in computers, including mercury, cadmium (also known carcinogen), and hexavalen Chromium (cause high blood pressure, iron-poor blood, liver disease, and nerve and brain damage in animals). Over 314 million computers were thrown away at the end of 2007.

Computer Recycling problem is, after upgrading computer system, most organizations store their old computers, which serve as backup equipment in case newer computers break down. decision must be made at some point about disposal of this equipment as continuing to store old computers is often not a viable option, it eventually takes up a considerable amount of space. The least desirable option is to throw old computers into the bin. computer recycling comes into the fore in every possible scenario, not just the effect it has upon the environment, there is also the possibility of someone removing hard drives and recovering sensitive data.

This drives to the point that data on hard disks should be destroyed - before getting rid of the computer or hard disk in it. Computer recycling isn't always about the environment, but of company and national safety importance too.

From an environmental point of view, it is far better to recycle your computer at an official recycling centre than to dispose of it.

B) OH+S considerations in the use of Computer Systems
Ergonomics is the term that refers to scitific discipline concerned with design according to human needs. It looks at what kind of work you do, what equipment you use and your entire job environment. The goal of ergonomics is to find best fit between you and your job conditions.

To setup an ergonomic computer workstation , make sure that teh computer is placed on a stable working surface with adequate room for proper arrangement. It's important to choose a comfortable chair for the user to sit in. Chair should be adjusted at a fixed height provided that its comfortable and has a good backrest that provides lumbar support.

A good workstation design will allow any computer user to work in a neutral, ideal typing posture that will minimize the risk of deveoping any injury.
A good workstation setup may include:
  • Ergonomics keyboards and mouse
  • Wrist rests
  • Support braces/gloves
Other considerations are the following environmental conditions where computer will be used
  • Lighting
  • Ventilation
  • Noise Take a break!
Make sure to practice the following to help avoid strain and injury
  • Eye breaks every 15 minutes
  • Rest breaks every 30 to 60 minutes.
  • Exercise break every 1-2 hours.

Internal hardware components, cost, image and function

Motherboard: the central printed circuit board (PCB) in many modern computers and holds many of the crucial components of the system, while providing connectors for other peripherals.
Asus P7P55D-E Pro
$206



Graphics Card: processing powerhouses, offloading from your CPU much of the hard work of calculating how scenes look, particularly in 3D graphics.
1GB 5850 Asus
$378


RAM: a form of computer data storage
2.5” Hitachi (Japanese Brand) SATA 320G
$63


CPU:the portion of a computer system that carries out the instructions of a computer program, and is the primary element carrying out the computer's functions.
Core i5-650
$215