CompTIA A+ • Mission 02
Before you replace or upgrade computer parts, understand what the parts do together. Investigate power, data, the motherboard, CPU, RAM, storage, bits and bytes, and safe hardware handling.
Mission 02 hands-on system
The Raspberry Pi 5 is part of Mission 02 because it gives you a complete computer you can identify, assemble, boot, inspect, and troubleshoot before moving to the larger desktop PC build.
Identify the Pi processor/SoC, soldered LPDDR memory, microSD and other storage options, USB-C power, HDMI, USB, Ethernet, Wi-Fi/Bluetooth, cooling, and GPIO. Compare each part with desktops, laptops, phones, and tablets.
Understand the Raspberry Pi 5Use the separate build guide for the physical assembly, boot-media preparation, first startup, verification, and troubleshooting steps. Separating the pages keeps the learning concepts from getting mixed up with the build procedure.
Open the Pi 5 build guideBy now, you should have reviewed the full A+ exam objectives, prepared your notebook area, started taking notes, and reviewed the course success information. Keep doing that work while you learn hardware.
Use the Pi 5 during this mission as a smaller computer you can inspect, assemble, boot, configure, and troubleshoot before Mission 03's full computer build. Compare its CPU, RAM, storage, power, display, USB, and network connections with the desktop components you are learning.
Notebook idea: make a two-column Pi 5 vs. desktop PC comparison. Focus on what performs the same function even when the form factor or connector is different.
Open the Raspberry Pi 5 build/use guideMission briefing
A computer uses electrical power and electrical signaling, but those ideas are not interchangeable. In this mission you will connect the physical machine to the bits, bytes, files, and speeds you see in A+.
The power supply converts incoming AC power into regulated DC outputs used by computer hardware. Motherboard voltage-regulation circuitry then provides the voltages required by specific components.
Digital hardware represents information with binary states. A bit is a 0 or 1. Hardware detects valid LOW and HIGH voltage ranges as logic states; the exact thresholds depend on the device and its electrical specification.
Core 1 hardware study includes power supplies, motherboards, CPUs, RAM, storage, connectors, and safe technician tools. Understanding their roles makes hardware installation and troubleshooting questions easier to reason through.
Use this simplified model. After the PSU and motherboard, power is distributed to multiple components; it does not have to pass through the CPU before reaching RAM or storage.
Electrical potential difference. PC power supplies commonly provide 12 V, 5 V, and 3.3 V DC rails, while onboard regulators create additional voltages needed by components.
Rate of electric charge flow. A device draws current according to the work it is doing and its electrical design.
Rate of energy use. For a DC load, power relates to voltage and current: watts = volts × amps.
Do not memorize one universal voltage for binary 0 and 1. Valid LOW/HIGH thresholds vary by technology, supply voltage, and component datasheet.
The motherboard connects the components and provides pathways for power, data, and control signals.
Holds a compatible processor and provides electrical connections between the CPU and motherboard.
Hold system RAM. Motherboard and CPU specifications determine supported memory type, capacity, speed, and channel configuration.
High-speed expansion connections for devices such as graphics, network, storage, and other adapter cards.
SATA connects many drives and optical devices. M.2 slots can support devices such as NVMe SSDs depending on the motherboard.
Executes instructions and performs calculations. Clock rate, cores, cache, architecture, workload, and other factors affect performance.
Fast, volatile working memory used for data and instructions needed by running processes. Its contents are lost when power is removed.
Nonvolatile storage keeps files when power is off. Common A+ examples include HDDs, SATA SSDs, and NVMe SSDs.
This is a teaching model. Modern systems can use caching, DMA, integrated graphics, and other optimizations, so real data paths can be more complex.
A bit stores one binary value. Eight bits form one byte. Bytes are grouped into larger units used to describe file and storage capacity.
01000001
8 bits = 1 byte. In ASCII, this byte represents the capital letter A. Text encodings such as Unicode can require different numbers of bytes for different characters.
Storage and memory capacity are commonly described in bytes and larger byte-based units: MB, GB, TB.
Network speeds are commonly stated in bits per second: Mb/s or Gb/s. File-copy speeds may be shown in bytes per second: MB/s or GB/s.
Electrostatic discharge can damage sensitive electronics. Use appropriate ESD controls and handle components by their edges when possible.
Shut down and disconnect equipment before internal service when appropriate. Do not open a power supply enclosure; hazardous energy can remain inside.
Build your study system
Mission 02 is where your notebook should become visual. Focus on what connects, where it connects, what it does, and the clues that help you distinguish similar hardware.
Title: Motherboard + CPU / RAM / Storage
Motherboard: Main circuit board. Connects hardware through power and data pathways. Label CPU socket, DIMM slots, M.2 slot, SATA ports, PCIe slots, main power connector, and rear I/O.
CPU: Executes instructions. Desktop Intel/AMD CPUs are typically socketed and replaceable; Raspberry Pi 5 uses a Broadcom BCM2712 Arm-based SoC soldered to the board.
RAM: Temporary/volatile working memory. Desktop systems use replaceable DIMMs; Pi 5 uses soldered LPDDR4X memory.
Storage: Keeps data after power is removed. Desktop PCs may use SATA or M.2/NVMe drives; Pi 5 commonly boots from microSD and can use PCIe-connected storage with the appropriate adapter.
Exam clue: Learn the connector + purpose together. A+ often describes the job or physical connection instead of simply naming the component.
Physical add-on: Tape in a safe short sample of an old cable, create a flap over a connector drawing, or add a removable label card.
This independent FamilyPD activity supports study of CompTIA A+ Core 1 hardware concepts, including motherboards, RAM, storage, power supplies, CPUs, connectors, tools, and hardware troubleshooting. It is a study aid, not an official CompTIA course or exam.
CompTIA and A+ are trademarks of CompTIA, Inc. Family Personal Development, Inc. is not affiliated with or endorsed by CompTIA unless expressly stated. Certification requirements and objectives can change; learners should compare study materials with the current official CompTIA exam objectives.
Next: Return to the A+ Learning Path and continue building your notebook as new missions are released.
