Core Hardware Components

Computing Fundamentals, Internal Components, and the Motherboard

Introduction to Core Hardware Components

Every computer—whether it is a desktop, laptop, tablet, smartphone, or server—is built from hardware components working together with software.

Regardless of how advanced the device is, every computer performs four basic operations:

  1. Input
  2. Processing
  3. Output
  4. Storage

These four functions form the foundation of modern computing.

Even cloud computing relies on physical hardware located in data centers around the world. Although users may never see these systems, cloud services still depend on processors, memory, storage devices, networking equipment, and motherboards.

The Four Basic Computing Functions

1. Input

Input is any data or instruction entered into a computer.

Common input devices include:

Examples

2. Processing

Processing occurs when the computer performs calculations or follows instructions.

The Central Processing Unit (CPU) performs nearly all processing tasks.

Examples include:

3. Output

Output is information produced after processing.

Common output devices include:

Example:

Typing on the keyboard (input) causes letters to appear on the monitor (output).

4. Storage

Storage preserves information for future use.

Storage devices include:

Unlike RAM, storage retains information after power is removed.

Exam Tip

Remember the basic computing cycle:

Input → Processing → Output → Storage

This is one of the most fundamental concepts on the CompTIA Tech+ exam.

Understanding Internal Computer Components

Inside every computer are several important hardware components.

The major internal components include:

Some components are essential for every computer, while others provide additional functionality.

Modular Hardware

Most desktop computers use modular hardware.

A modular component can be:

Examples include:

These replaceable parts are called Field Replaceable Units (FRUs).

Benefits

Non-Modular Devices

Smaller devices usually integrate components directly onto the motherboard.

Examples include:

Because components are integrated, repairs are often difficult or impossible.

The Computer Case

Although often overlooked, the computer case serves several critical functions.

Functions

1. Protects Components

Protects against:

2. Holds Components Securely

Keeps all internal hardware properly mounted.

3. Provides Cooling

Allows airflow to prevent overheating.

Modern cases use:

Motherboard Overview

The motherboard is the most important circuit board inside a computer.

Other names include:

It serves as the communication center for every hardware component.

Without the motherboard, the CPU, RAM, storage devices, and expansion cards cannot communicate.

Functions of the Motherboard

The motherboard:

Think of it as the computer’s highway system.

Every piece of information travels through the motherboard.

Printed Circuit Board (PCB)

A motherboard is a Printed Circuit Board (PCB).

A PCB consists of conductive pathways printed onto a nonconductive surface.

These pathways carry electrical signals between hardware components.

Most PCBs are green, although black, blue, white, red, and other colors are common.

Major Motherboard Components

A typical motherboard contains:

Each component performs a specific task.

Motherboard Form Factors

A form factor defines:

The motherboard form factor must match the computer case.

Common Form Factors

ATX (Advanced Technology Extended)

The most common desktop motherboard.

Advantages

Common Uses

MicroATX (mATX)

A smaller version of ATX.

Advantages

Disadvantages

Common Uses

Mini-ITX

Very small motherboard.

Advantages

Disadvantages

Common Uses

Motherboard Form Factor Comparison
FeatureATXMicroATXMini-ITX
SizeLargestMediumSmallest
Expansion SlotsManyModerateOne
Upgrade PotentialExcellentGoodLimited
Typical UseGaming & WorkstationsHome & OfficeCompact PCs
Chipset

The chipset is a collection of integrated circuits that controls communication between hardware devices.

It determines:

Think of the chipset as the motherboard’s traffic controller.

Northbridge vs Southbridge

Older motherboards divided chipset functions into two major sections.

Northbridge

Handled high-speed communication.

Responsible for:

Southbridge

Handled slower devices.

Responsible for:

Modern Motherboards

Most modern computers no longer use separate Northbridge and Southbridge chips.

Instead, manufacturers combine these functions into:

This design improves performance, reduces power consumption, and simplifies motherboard architecture.

Computer Buses

A bus is a communication pathway that transfers data between computer components.

It acts like a highway carrying information between devices.

There are two main types:

Parallel Bus

Examples:

Serial Bus

Examples:

Parallel vs. Serial Bus Comparison
FeatureParallel BusSerial Bus
Data TransferMultiple bits simultaneouslyOne bit at a time
SpeedSlower in modern systemsFaster
ComplexityHigherLower
Current UseLegacy devicesModern computers

Key Terms to Remember

Exam Tips

CPU Sockets, Memory Slots, Expansion Slots, BIOS, and Motherboard Components

CPU (Processor) Socket

The CPU socket is a specially designed connector on the motherboard that securely holds the processor and provides the electrical connections required for communication between the CPU and the rest of the computer.

Because processors are manufactured in different sizes and pin layouts, the motherboard socket must exactly match the processor. A processor designed for one socket type cannot be installed in another.

Purpose of the CPU Socket

The CPU socket performs several important functions:

Without the correct socket, the processor cannot function.

Common CPU Socket Types

Pin Grid Array (PGA)

In a PGA (Pin Grid Array) design:

Advantages

Disadvantages

Land Grid Array (LGA)

Modern Intel processors primarily use LGA (Land Grid Array) sockets.

In this design:

Advantages

Disadvantages

Ball Grid Array (BGA)

BGA processors are permanently attached (soldered) to the motherboard.

Commonly found in:

Advantages

Disadvantages

Exam Tip

Always verify CPU compatibility with the motherboard socket before upgrading a processor.

CPU Cooling

Processors generate a tremendous amount of heat while operating.

Without cooling, a CPU can overheat within seconds.

Most systems use one or more cooling devices:

Heat Sink

A heat sink is a metal device with fins that transfers heat away from the processor.

Common materials include:

The fins increase surface area, allowing heat to dissipate more efficiently.

CPU Fan

A CPU fan blows cool air across the heat sink.

Together, the fan and heat sink keep processor temperatures within safe operating limits.

Thermal Paste

Thermal paste fills microscopic air gaps between the CPU and heat sink.

Benefits include:

Memory Slots

Memory slots hold the computer’s Random Access Memory (RAM) modules.

RAM stores programs and data that are currently being used by the CPU.

Because RAM is much faster than storage devices, the processor retrieves active information directly from RAM.

Characteristics of RAM Slots

Memory slots are:

Desktop motherboards usually contain:

DIMM

Desktop computers use:

DIMM
(Dual Inline Memory Module)

Characteristics:

Modern DIMMs support:

SODIMM

Laptop computers use:

SODIMM
(Small Outline Dual Inline Memory Module)

Characteristics:

DIMM vs SODIMM
FeatureDIMMSODIMM
Used InDesktopLaptop
Physical SizeLargerSmaller
CapacityHigherModerate
UpgradeabilityEasyEasy (most laptops)
Cache Memory

Cache memory is extremely fast memory located very close to or inside the processor. Its purpose is to reduce the amount of time required for the CPU to access frequently used information. Instead of retrieving data from slower RAM, the CPU checks cache memory first.

Levels of Cache

L1 Cache

L2 Cache

L3 Cache

Cache Hierarchy

Fastest → Slowest

L1 Cache

↓

L2 Cache

↓

L3 Cache

↓

RAM

↓

Storage (SSD/HDD)

Expansion Slots

Expansion slots allow users to install additional hardware to increase a computer’s capabilities.

Examples include:

PCI (Peripheral Component Interconnect)

PCI was the standard expansion slot for many years.

Characteristics:

Supported:

Today, PCI is considered legacy technology.

AGP (Accelerated Graphics Port)

AGP was designed specifically for graphics cards.

Advantages over PCI:

AGP has now been replaced by PCI Express.

PCI Express (PCIe)

PCI Express is the modern expansion slot standard.

It is:

PCIe uses serial communication rather than parallel communication.

Common PCIe Sizes

PCIe x1

Used for:

PCIe x4

Used for:

PCIe x8

Used for:

PCIe x16

Primarily used for:

PCIe Advantages
PCIe Comparison
SlotTypical Use
x1NIC, Sound Card
x4Storage Controllers
x8Enterprise Devices
x16Graphics Cards
Disk Controllers

Disk controllers allow storage devices to communicate with the motherboard.

IDE (PATA)

Older interface.

Characteristics:

Now considered obsolete.

SATA (Serial ATA)

Current standard for HDDs and SSDs.

Advantages:

M.2

M.2 is a compact connector for SSDs.

Benefits:

NVMe

Many M.2 drives use:

NVMe
(Non-Volatile Memory Express)

NVMe communicates directly through PCI Express lanes.

Advantages:

Power Connectors

The motherboard receives power from the power supply using a 24-pin ATX connector.

Additional connectors provide power for:

Without these connections, the system cannot operate.

BIOS

BIOS
(Basic Input/Output System)

BIOS is firmware stored on the motherboard.

Its responsibilities include:

POST

POST stands for:

Power-On Self-Test

Every time a computer starts, POST checks hardware including:

If a problem is found:

may indicate the fault.

UEFI

Modern computers use:

UEFI
(Unified Extensible Firmware Interface)

Advantages over BIOS:

Bios Configuration

Users can access BIOS or UEFI during startup to:

Flashing the BIOS

Flashing updates motherboard firmware.

Reasons to update:

Warning: A failed BIOS update can make the motherboard unusable.

CMOS

CMOS stores BIOS configuration settings such as:

CMOS Battery

The CMOS battery supplies power to preserve BIOS settings when the computer is turned off.

Signs of a failing CMOS battery:

Replacement is simple and inexpensive.

Front Panel Connectors

Common front-panel components include:

These improve accessibility for everyday use.

Back Panel Connectors

Typical motherboard rear connectors include:

These allow users to connect external peripherals.

Key Terms:

Exam Tips

Processors, Memory, Storage Devices, Graphics, and Networking

Processor (CPU)

The Central Processing Unit (CPU) is the primary processing component of a computer. It executes program instructions, performs calculations, and coordinates the activities of nearly every hardware component in the system. Because it controls the execution of instructions and processes data, the CPU is commonly referred to as the “brain of the computer.”

The terms CPU and processor are used interchangeably.

Modern processors are manufactured using millions—or even billions—of microscopic transistors etched onto a silicon chip. These transistors act as tiny electrical switches that process binary data (1s and 0s), allowing the CPU to perform calculations at extremely high speeds.

The two dominant manufacturers of PC processors are:

Both companies produce processors for desktops, laptops, workstations, servers, and gaming systems.

CPU Functions

The processor performs several critical tasks within a computer system:

Without a functioning processor, a computer cannot operate.

CPU Characteristics

When comparing processors, several characteristics determine their performance and compatibility.

The most important include:

Processor Architecture

Processor architecture describes how a CPU is designed to process information.

The three architectures most commonly encountered in modern computing are:

32-bit Architecture

A 32-bit processor processes 32 bits of data at one time.

Characteristics include:

Although still encountered in older devices, 32-bit processors have largely been replaced by 64-bit models.

64-bit Architecture

A 64-bit processor processes 64 bits of data simultaneously.

Compared with 32-bit processors, 64-bit CPUs offer:

Today, virtually all new desktop and laptop computers use 64-bit processors.

ARM Architecture

ARM (Advanced RISC Machines) processors use a Reduced Instruction Set Computing (RISC) architecture.

Unlike traditional desktop processors, ARM processors are designed to maximize energy efficiency while minimizing heat generation.

Advantages

Common Devices

Approximately 90% of mobile devices use ARM-based processors.

RISC vs. CISC

Modern processors generally follow one of two instruction set philosophies.

RISCCISC
Reduced Instruction Set ComputingComplex Instruction Set Computing
Simpler instructionsMore complex instructions
Lower power consumptionHigher performance for complex tasks
Used by ARMUsed by Intel and AMD x86/x64 processors

For the CompTIA Tech+ exam, remember that ARM processors use a RISC architecture and are common in mobile devices.

Multi-Core Processors

Early computers contained only a single processing core.

Modern CPUs contain multiple cores that can execute instructions simultaneously.

Common configurations include:

Benefits

Multiple cores improve:

Clock Speed

Clock speed measures how quickly a processor executes instructions.

It is measured in:

Examples:

Generally, a higher clock speed allows a processor to execute more instructions each second, although overall performance also depends on architecture, cache, and core count.

CPU Throttling

Modern processors can automatically reduce their operating speed when:

This feature is called CPU throttling and helps reduce power consumption and heat generation.

Cache Memory Review

Cache memory stores frequently accessed instructions and data so the processor can retrieve them much faster than from RAM.

Cache Hierarchy
Cache LevelCharacteristics
L1Smallest and fastest; located within each CPU core
L2Larger than L1; slightly slower; usually dedicated to each core
L3Largest cache; shared among CPU cores; slower than L1 and L2 but much faster than RAM

Memory is accessed in the following order:

L1 → L2 → L3 → RAM → Storage

Understanding Computer Memory

Memory temporarily stores data and instructions that the processor needs while the computer is running.

Memory chips store information using binary values (0s and 1s).

Volatile vs. Non-Volatile Memory

Volatile Memory

Volatile memory loses its contents when electrical power is removed.

Example:

Non-Volatile Memory

Non-volatile memory retains data even when power is turned off.

Examples:

ROM (Read-Only Memory)

ROM permanently stores firmware and system instructions.

Characteristics:

Modern systems commonly use EEPROM (Electrically Erasable Programmable ROM), allowing firmware updates without replacing the chip.

RAM (Random Access Memory)

RAM temporarily stores:

RAM is the computer’s primary working area while it is powered on.

The more RAM a computer has, the more applications it can run efficiently at the same time.

SRAM vs. DRAM

SRAM (Static RAM)

Characteristics:

DRAM (Dynamic RAM)

Characteristics:

Virtual Memory

When physical RAM becomes full, the operating system uses virtual memory.

Virtual memory reserves part of the storage drive to temporarily hold data that cannot fit into RAM.

This reserved area is known as the:

Advantages

Disadvantages

Adding more physical RAM is usually a better solution than relying on virtual memory.

DDR Memory Generations

Modern computers use DDR (Double Data Rate) SDRAM.

Each generation improves speed while reducing power consumption.

GenerationImprovements
DDRFirst generation
DDR2Faster, lower power
DDR3Higher bandwidth
DDR4Greater efficiency and speed
DDR5Highest performance, lower power consumption

Important: Motherboards support only specific DDR generations. DDR modules are keyed differently and are not interchangeable.

Storage Devices

Unlike RAM, storage devices preserve information even when the computer is powered off.

Common storage devices include:

Hard Disk Drive (HDD)

An HDD stores information magnetically on spinning platters.

Advantages

Disadvantages

Typical desktop HDDs use 3.5-inch drives, while laptops commonly use 2.5-inch drives.

Common spindle speeds include:

Higher RPM generally means faster data access.

Solid-State Drive (SSD)

An SSD stores information using flash memory instead of spinning disks.

Advantages

Disadvantages

NVMe SSD

NVMe (Non-Volatile Memory Express) SSDs communicate directly through PCI Express lanes.

Compared to SATA SSDs, NVMe drives provide:

Optical Storage

Optical drives use lasers to read and write data.

Common formats include:

Although less common today, optical media are still used for software distribution, media playback, and archival storage.

USB Flash Drives

USB flash drives use non-volatile flash memory.

Advantages include:

They are commonly used for transferring files and creating bootable installation media.

Storage Capacity Units

Understanding storage units is essential for the CompTIA Tech+ exam.

UnitEquivalent
1 Byte8 bits
1 KB1,000 bytes
1 MB1,000 KB
1 GB1,000 MB
1 TB1,000 GB
1 PB1,000 TB

Know the order from bit → byte → KB → MB → GB → TB → PB.

Graphics Processing Unit (GPU)

The Graphics Processing Unit (GPU) renders images, animations, and video.

Two types of GPUs are commonly used:

Integrated GPU

Dedicated GPU

Network Interface Card (NIC)

A Network Interface Card (NIC) enables a computer to communicate over a network.

Two common types are:

Wired NIC

Uses an Ethernet cable.

Advantages:

Wireless NIC

Uses Wi-Fi.

Advantages:

Onboard vs. Expansion Devices

Modern motherboards often include built-in components such as:

Expansion cards are installed when additional performance or features are required.

Examples include:

Summary

By the end of this chapter, you should understand:

Quick Review
Final Exam Tips