CompTIA A+ Master Cheat Sheet – Hardware & Operational Review

These QUESTION_AND_ANSWER flashcards cover key CompTIA A+ 220-1001/1002 hardware, networking, security, OS, and troubleshooting concepts for rapid exam review.

What is the maximum length of an Ethernet cable segment?

100 meters

Which Ethernet category supports 10 Gbps up to 55 m and 1 Gbps up to 100 m?

Category 6 (Cat 6)

What is the main safety benefit of plenum-rated cable?

Uses low-smoke, low-flame materials to reduce fire hazards in HVAC plenum spaces

How do shielded twisted-pair (STP) cables reduce electromagnetic interference?

By adding a foil or braided shield around the pairs

Which termination standard is used on crossover cables?

568A on one end and 568B on the other

What medium does fiber-optic cable use to transmit data?

Light pulses through glass or plastic core

Single-mode fiber is typically sourced by what type of light emitter?

Laser

What are the two most common coaxial cable designations and their primary uses?

RG-6 for data (cable Internet) and RG-59 for audio/video (cable TV)

Which video connector uses 15 pins in three rows?

VGA

What is the primary difference between DVI-D and DVI-I?

DVI-D carries only digital signals; DVI-I carries both digital and analog

Apple’s proprietary eight-wire reversible cable is known as what?

Lightning

What is the maximum total throughput of Thunderbolt 3?

40 Gbps

Which USB version introduced 480 Mbps High-Speed mode?

USB 2.0

How many devices can be attached to a single SCSI chain?

Up to 16

Which connector is trapezoid-shaped and has 9 pins arranged in two rows?

DB-9 (RS-232)

What does SODIMM stand for?

Small Outline Dual Inline Memory Module

How many pins are on a DDR4 DIMM?

288 pins

Which RAM architecture moves data on two 64-bit buses simultaneously?

Dual Channel

What feature allows ECC memory to correct single-bit errors?

Parity bit combined with error-correcting logic

How much data can a single-layer DVD-ROM hold?

4.7 GB

What is the main advantage of solid-state drives (SSD) over magnetic drives?

No moving parts → faster access and greater reliability

Name two common spindle speeds for magnetic HDDs.

5,400 rpm and 7,200 rpm (others include 10,000 & 15,000 rpm)

What RAID level provides striping with no redundancy?

RAID 0

What is the minimum number of drives required for RAID 5?

Three

Which motherboard form factor measures 6.7 × 6.7 inches?

Mini-ITX (mITX)

What is the purpose of a riser card?

Adds expansion slots at 90° to fit cards in a low-profile case

What BIOS option prevents booting with unsigned OS files and drivers?

Secure Boot

What chip stores cryptographic keys for drive encryption?

TPM – Trusted Platform Module

Why might you replace a CMOS battery today?

To keep the real-time clock running

What CPU feature lets a single core appear as two virtual cores?

Hyper-Threading

Running a CPU faster than its rated speed is called what?

Overclocking

Which cooling method circulates distilled water through a radiator and block?

Liquid cooling

What expansion card adds additional USB ports?

USB expansion card

Which custom PC build benefits most from dual monitors and large fast storage?

Audio/Video Editing Workstation

What NIC speed is recommended for a NAS device?

Gigabit NIC (1 Gbps)

Thin clients must meet what level of OS requirements?

Minimum requirements only

Which power-supply connector delivers DC to the motherboard?

24-pin ATX connector

In North America, wall outlets supply what AC voltage range?

110–120 V AC

What does a KVM switch allow?

One keyboard, video monitor, and mouse to control multiple computers

Which print technology uses toner fused by heat and pressure?

Laser printing

Name the six laser printing imaging steps in order.

Processing, Charging, Exposing, Developing, Transferring, Fusing, Cleaning

What component flips paper for duplex printing in laser/inkjet printers?

Duplexing assembly

Thermal printers require what special consumable?

Heat-sensitive thermal paper

Dot-matrix printers create images using what part?

Print head with a matrix of pins striking an ink ribbon

What 3-D printing material feeds through a heated nozzle?

Plastic filament

Which Windows command lists directory contents?

dir

Which CLI tool shows current IP configuration in Windows?

ipconfig

What Windows utility manages startup programs on the Startup tab?

Task Manager (or MSConfig → Startup in older versions)

Which command repairs corrupted Windows system files?

sfc /scannow

What Windows feature encrypts an entire drive on Windows Pro/Enterprise?

BitLocker

Which Linux command changes the current directory?

cd

How do you list running processes in Linux?

ps

Which mobile OS is based on the Linux kernel and developed by Google?

Android

What is the purpose of MDM policies?

Remotely manage and secure mobile devices used for work

What does the principle of least privilege state?

Users receive the minimum permissions required to perform their jobs

What are the two common wireless security protocols that replaced WEP?

WPA and WPA2 (using TKIP/AES respectively)

A fraudulent email pretending to be legitimate is an example of what attack?

Phishing

What device adds encrypted tunnel capability between networks?

VPN (Virtual Private Network) appliance

Name the nine‐step best-practice malware removal process.

Identify symptoms → Quarantine → Disable restore → Remediate → Schedule scans → Enable restore → Create restore point → Educate user

Which Windows utility creates a full system image for recovery?

Backup and Restore (Windows Image) / System Image Backup

What is a mantrap used for in physical security?

Controls entry by isolating individuals between two locking doors

Why use surge suppressors with computer equipment?

Divert voltage spikes to ground, protecting devices

Which regulation governs electronic health information in the U.S.?

HIPAA (Health Insurance Portability and Accountability Act)

What is the purpose of an entry control roster?

Logs everyone who enters or exits a secured area

What should be done first when troubleshooting?

Identify the problem and interview the user

What is the maximum cable length for a Thunderbolt copper cable?

3 meters

Which command in Windows displays all listening TCP/UDP ports?

netstat -a

What type of backup only copies changes since the last full backup?

Incremental backup

How many devices can a single USB root hub support?

127

Which cloud model provides virtual hardware like VMs and storage?

IaaS – Infrastructure as a Service

What file extension identifies a Windows PowerShell script?

.ps1

Name two authentication factors used in multifactor authentication.

Something you know (password), something you have (token), something you are (biometrics), etc.

What is the first step after receiving a mobile device showing no power?

Verify the battery is charged and the power source works

Which feature in macOS shows all open windows and desktops?

Mission Control

Describe chmod 755 in Linux permissions.

Owner: read/write/execute; Group & Others: read/execute

What tool in macOS backs up data to an external drive automatically?

Time Machine

Which virtualization type runs directly on host hardware without a host OS?

Type 1 hypervisor (bare-metal)

What Windows feature allows sharing of files with minimal configuration on home LANs?

HomeGroup (Windows 7/8)

Which printer issue is indicated by toner easily rubbing off the page?

Fuser assembly failure

Name the Windows tool used to add, remove, or repair installed programs.

Programs and Features (Add or Remove Programs)

What class of Bluetooth is intended for mobile devices with 10-m range?

Class 2

What is the default TCP port for RDP?

3389

Which Windows CLI command forcefully stops a running process by PID?

taskkill /PID /F

How does a proxy server enhance security?

Acts as intermediary, filtering and caching web traffic

What Linux command copies files and directories?

cp

Which UPS characteristic measures how long it can power equipment?

Battery capacity/runtime

What happens after 10 failed login attempts on an iPhone if not disabled?

Device wipes all data

Which RAID level combines mirroring and striping for full redundancy?

RAID 10

Where in Windows can you enable or disable Device drivers?

Device Manager

What is required to access encrypted EFS files after a profile is rebuilt?

User’s original encryption certificate/key or recovery agent

Which file attribute keeps files from accidental deletion but allows reading?

Read-only attribute

Why disable AutoRun/AutoPlay on Windows systems?

Prevents automatic execution of potentially malicious media

Which tool produces a tone to trace a cable run in a wiring closet?

Tone generator and probe (fox & hound)

How is APIPA address range identified?

169.254.0.0/16

What mobile feature allows turning off Wi-Fi, Bluetooth, and cellular at once?

Airplane Mode

Which Windows folder holds 32-bit system files on a 64-bit OS?

C:\Windows\SysWOW64

What command in Linux shows network interface configuration?

ifconfig (or ip addr)

Explain the advantage of M.2 NVMe SSD over SATA SSD.

Uses PCIe lanes for much higher throughput and lower latency

Which printer component in an inkjet moves cartridges across the paper?

Carriage (with belt drive)

Name two built-in Windows Remote Management tools.

Remote Desktop (RDP) and Windows Remote Assistance