IGCSE ICT 0417 - Types and Components of Computer Systems

Objective: Know and understand characteristics of a desktop computer

What is a Desktop Computer?

A desktop computer is a personal computer designed for use on or a desk. It is typically composed of separate components, including a system unit (tower), monitor, keyboard, and mouse. Desktop computers are known for their power, flexibility, and ease of upgrading.

Key Characteristics of a Desktop Computer

• Modular Design: Desktop computers are built from separate, interchangeable components. This allows for customization and upgrades.
• Power: Generally offer more processing power than laptops due to better cooling capabilities and access to larger power supplies.
• Expandability: Easy to add or replace components like RAM, hard drives, graphics cards, and expansion cards.
• Customization: Users can choose and configure components to meet specific needs and budgets.
• Ergonomics: Can be set up with ergonomic peripherals (keyboard, mouse, monitor) for comfortable use.
• Connectivity: Typically offer a wide range of ports for connecting peripherals and external devices.
• Cost-Effective: Often provide better performance per pound compared to laptops in the same price range.

Main Components of a Desktop Computer

A desktop computer consists of several key components working together. Here's a breakdown:

Component	Description	Function
System Unit (Tower)	The main housing for the computer's internal components.	Contains the motherboard, CPU, RAM, storage devices, and power supply.
Motherboard	The main circuit board that connects all the components.	Provides pathways for communication between components.
CPU (Central Processing Unit)	The "brain" of the computer.	Executes instructions and performs calculations.
RAM (Random Access Memory)	Temporary storage for data and instructions being actively used.	Allows for quick access to information.
Storage Devices (HDD/SSD)	Used for permanent storage of data, applications, and the operating system.	HDDs (Hard Disk Drives) and SSDs (Solid State Drives) store data persistently.
Graphics Card (GPU)	Processes and outputs images to the monitor.	Improves graphics performance for gaming, video editing, and other visual tasks.
Power Supply Unit (PSU)	Converts AC power from the wall outlet to DC power used by the computer components.	Provides the necessary power to all components.
Monitor	Displays the output from the computer.	Allows the user to see the results of their work.
Keyboard	Used for inputting text and commands.	Allows the user to interact with the computer.
Mouse	Used for pointing and selecting items on the screen.	Provides a way to navigate the graphical user interface.

Advantages of Desktop Computers

• High performance
• Easy to upgrade
• Wide range of components
• Good value for money
• Suitable for demanding tasks

Disadvantages of Desktop Computers

• Not portable
• Requires a dedicated workspace
• Can be bulky