Inside a PC: Components and Devices

• newEditor
• Computing
• Upper Secondary (Key Stage 4)
• BTEC

Open with the idea that students use devices every day, but the performance they experience comes from a small set of hardware components working together.

Learning goal

I can identify the main components inside a PC and explain how their specifications affect performance, including storage types and common external devices.

Which PC parts or devices do you already know?

Use this to surface prior knowledge. Expect terms such as CPU, RAM, GPU, SSD, HDD, monitor, printer and router. Briefly sort answers into internal components and external devices.

What is inside a PC?

• A PC is made of hardware components

• Each component has a different job

• Some parts process data, some store it, and some send output

• Knowing the parts helps you compare computers

Keep the distinction simple: internal components are inside the system unit; peripherals such as monitors and printers connect to it.

Main internal components

• CPU: carries out instructions

• RAM: holds data being used right now

• GPU: handles graphics and visual processing

• Storage: keeps files and software

• Motherboard: connects the components together

• Power supply: provides electrical power

The motherboard and power supply are included for context, but the lesson focus is CPU, RAM, GPU and storage.

How components work together

• Programs are loaded from storage into RAM

• The CPU processes instructions

• The GPU creates images for the screen

• Results are saved back to storage or shown on output devices

This is the key system view of the lesson. Reinforce that speed depends on more than one part, not only the CPU.

Performance depends on specification

A specification is a measured detail about a component, such as capacity, speed or number of cores. Higher specifications often improve performance, but the best choice depends on the task being done.

Students often assume 'bigger number = always better'. Point out that suitable specification depends on gaming, office work, browsing or media editing.

Which part carries out instructions from programs?

A

CPU

B

RAM

C

Storage

D

Monitor

Checks the core role of the CPU and distinguishes it from memory, storage and output devices.

CPU: the processor

• CPU stands for Central Processing Unit

• It is often called the 'brain' of the computer

• It runs instructions from programs

• It performs calculations and controls other operations

CPU specifications

• Clock speed: how many cycles the CPU can perform each second, measured in GHz

• Cores: separate processing units inside one CPU

• Threads: tasks the CPU can manage at once

• More cores can improve multitasking and demanding software

Avoid over-technical detail. At this level, it is enough that GHz relates to speed and cores relate to handling multiple tasks.

CPU speed in context

• A higher GHz can mean faster processing

• A CPU with more cores may perform better in multitasking

• Performance also depends on cooling, software and the other components

• A fast CPU can still feel slow if RAM or storage is limited

This slide corrects the common misconception that one specification tells the whole story.

RAM: working memory

• RAM stands for Random Access Memory

• It stores data the computer is using now

• It is temporary memory

• When the power is turned off, RAM is cleared

Students often confuse RAM with storage. Emphasise that RAM is short-term and storage is long-term.

RAM specifications

• Capacity is measured in GB

• Common sizes include 8 GB, 16 GB and 32 GB

• More RAM helps when using many programs at once

• RAM also has a speed rating, which affects how quickly data can be accessed

You do not need to teach exact RAM standards in depth; focus on capacity and the idea that memory speed exists.

What more RAM improves

• Smoother multitasking

• Better performance in large applications

• Less slowing down when many browser tabs are open

• Improved responsiveness when enough RAM is available

Clarify that adding RAM helps only up to a point. If there is already enough RAM for the task, another component may be the limit.

What is clock speed usually measured in?

A

GB

B

TB

C

GHz

D

ppm

GB and TB are storage or memory capacity units; ppm is a printer measure.

What usually helps a computer handle many tasks at once?

A

More printer speed

B

More RAM

C

Higher resolution

D

Bigger monitor

Targets the idea that extra RAM supports multitasking and many open programs or tabs.

CPU and RAM in context

A higher GHz can mean faster CPU processing. More cores may improve multitasking. RAM capacity is measured in GB, and RAM is temporary memory.

GHz

cores

GB

temporary

TB

permanent

resolution

VRAM

Reinforces the separate ideas of CPU speed, CPU cores, RAM capacity and temporary memory.

GPU: graphics processing

• GPU stands for Graphics Processing Unit

• It processes images, video and 3D graphics

• It helps display smooth visuals on a monitor

• It is especially important for gaming, design and video editing

GPU specifications

• VRAM stores graphic data for quick access

• Clock speed affects processing speed

• A more powerful GPU can render higher-quality graphics

• Some computers use integrated graphics, while others use a dedicated GPU

Integrated graphics are built into the CPU or motherboard area; a dedicated GPU is a separate component with its own processing power.

When the GPU matters most

• Watching video: modest graphics needs

• Office work: usually low graphics demand

• Gaming: high graphics demand

• 3D modelling and editing: often benefit from a stronger GPU

Use examples students know, such as gaming versus writing a document, to make the specification choices meaningful.

Which task needs a stronger GPU most?

A

Writing documents

B

Browsing emails

C

Gaming

D

Saving files

Tests application of the GPU slides to real use cases students recognise.

Storage: keeping files

• Storage keeps data even when power is off

• It stores the operating system, software and user files

• Capacity is usually measured in GB or TB

• Two common types are HDD and SSD

HDD: Hard Disk Drive

• Uses spinning magnetic disks

• Usually offers large capacity for a lower price

• Slower to read and write data than SSD

• Contains moving parts, so it is more easily damaged by knocks

If useful, mention that HDDs were very common in older PCs and are still used for large, cheaper storage.

SSD: Solid State Drive

• Uses flash memory and has no moving parts

• Faster start-up, loading and file access

• Usually more expensive per GB than HDD

• Often improves the overall feel of a computer

Students often notice boot speed first. Link SSD performance to everyday experience such as opening apps faster.

HDD and SSD compared

HDD

• Larger capacity for less cost

• Slower performance

• Better for bulk storage

SSD

• Faster performance

• Higher cost per GB

• Better for speed and responsiveness

If space allows in delivery, note that many computers use both: SSD for the operating system and HDD for large files.

Storage speed and capacity

• Capacity tells you how much data can be stored

• Read speed affects how quickly files open

• Write speed affects how quickly files save

• Fast storage reduces loading times but does not replace RAM or CPU power

This slide helps separate the ideas of size and speed, which students often mix up.

Which storage type has no moving parts?

A

HDD

B

SSD

C

RAM

D

VRAM

Checks the key HDD versus SSD contrast.

What does storage capacity tell you?

A

Image sharpness

B

How much data fits

C

How fast pages print

D

How many cores exist

Separates capacity from speed and from unrelated specifications.

Devices connected to a PC

• Not all hardware is inside the PC

• Some devices connect to send input, show output or provide network access

• Common examples include the monitor, printer and router

Bridge from internal components to external devices so the lesson fits the teacher's requested device coverage.

Monitor

• A monitor is an output device

• It displays text, images and video

• Important specifications include screen size, resolution and refresh rate

• Higher resolution can produce a sharper image

Keep refresh rate simple: more updates per second can make motion look smoother.

Printer

• A printer produces a paper copy of digital work

• It is an output device

• Specifications may include print speed and print quality

• Some printers are designed for text, while others are better for colour images

You may mention ppm as pages per minute if students have seen printer specifications before.

Router

• A router connects devices to a network

• It often provides access to the internet

• It sends data between the local network and other networks

• Speed and signal strength affect connection quality

Students may confuse a router with a modem; keep the focus on the router's role in directing network traffic.

Choosing the right hardware

• Office work may need a modest CPU, enough RAM and basic graphics

• Gaming often needs a stronger GPU, a capable CPU and fast storage

• Large media files may need high-capacity storage

• Good choices depend on what the computer is meant to do

This slide resolves the central question: specifications matter because they must match the user's needs.

Which device directs data between networks?

A

Printer

B

Router

C

Monitor

D

GPU

Distinguishes the router from output devices and internal components.

Which spec matters most for a sharper monitor image?

1

Resolution

2

Print speed

3

Signal strength

4

Cores

Glossary

CPU - The component that processes instructions and controls operations.

RAM - Temporary memory that stores data currently in use.

GPU - The component that processes graphics, images and video.

Storage - Hardware that keeps files and software even when power is off.

HDD - A storage device that uses spinning disks to save data.

SSD - A storage device that uses flash memory and has no moving parts.

Specification - A measured detail such as speed, capacity or number of cores.

Glossary

Clock speed - The rate at which a processor works, usually measured in GHz.

Core - An individual processing unit inside a CPU.

VRAM - Memory used by a GPU to store graphic data.

Resolution - The number of pixels on a screen, affecting image sharpness.

Refresh rate - How many times per second a monitor updates the image.

Router - A device that directs data between networks.

Peripheral device - A device connected to a computer, such as a monitor or printer.