Overview
Hardware is Core 1 (220-1201) domain 3.0 and carries 25% of that exam across eight objectives. It covers display types and attributes (IPS, TN, VA, OLED, Mini-LED, refresh rate, color gamut), cable types and connectors from Cat 6a and fiber to HDMI and Thunderbolt, RAM form factors, DDR generations, ECC and channels, storage interfaces and RAID levels, motherboard form factors, BIOS/UEFI settings, CPUs and expansion cards, power supply voltages and wattage, and the setup and maintenance of laser, inkjet, thermal and impact printers and multifunction devices.
Candidates must choose compatible parts and the right setting for a stated requirement, such as a RAID level that survives two drive failures or a cable rated for a ceiling air space. Everything here returns in Core 1 domain 5.0 as symptoms, so this domain is the reference model for troubleshooting.
How it's tested
Questions are mostly compatibility and selection decisions: a requirement or constraint is given and you choose the part, cable, RAID level or setting that satisfies all of it. Watch for qualifiers like most fault tolerant, lowest cost, plenum space or longest distance. Performance-based items may ask you to match connectors to images or order printer process steps.
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Meet every constraint
A build or upgrade lists several requirements, such as capacity, redundancy, budget or form factor, and only one option satisfies all of them.
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Identify by description
A connector, panel type or memory feature is described by its traits and you name it, such as a keyed, screw-in serial connector being DB9.
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Maintenance for the technology
A printer type and its symptom or schedule are given, and you pick the correct consumable or maintenance task for that technology.
A small business wants four drives in a file server, needs the array to survive any two drives failing, and wants as much usable space as that allows. RAID 10 can survive two failures only if they hit different mirrors, so it does not guarantee it. RAID 5 survives only one. RAID 6 uses two drives' worth of parity and survives any two failures, so it is the answer.
Objectives 8
Official objectives from the CompTIA outline, in outline order.
3.1 Compare and contrast display components and attributesLCD panel types, OLED, Mini-LED, touch digitizers and display specifications.
- What it means
- Covers LCD panel types (in-plane switching, twisted nematic, vertical alignment), organic LED, Mini-LED, touch screen digitizers and inverters, and the attributes pixel density, refresh rate, screen resolution and color gamut.
- What to understand
- IPS gives the best color accuracy and viewing angles, TN is the fastest and cheapest but shifts color at angles, and VA sits between with high contrast. OLED pixels emit their own light for true blacks but can suffer burn-in. Mini-LED is an LCD with thousands of small backlight LEDs in dimming zones. An inverter powers older CCFL backlights and is absent from LED-backlit panels.
- How it shows up
- A graphic designer, a gamer or a kiosk has a stated priority and you choose the panel type or attribute that matches.
- Common confusion
- Treating Mini-LED as a form of OLED. Mini-LED is still an LCD with a finer backlight; OLED has no backlight at all.
3.2 Summarize basic cable types and their connectors, features, and purposesNetwork, peripheral, video and storage cables and their connectors.
- What it means
- Covers copper network cable categories, T568A and T568B wiring, coaxial cable, shielded and unshielded twisted pair, direct burial and plenum ratings, single-mode and multimode fiber, USB 2.0 and 3.0, serial, Thunderbolt, HDMI, DisplayPort, DVI, VGA, USB-C, SATA, eSATA, and connectors such as RJ11, RJ45, F-type, ST, SC, LC, punchdown, Molex, Lightning and DB9.
- What to understand
- Cat 5e supports 1 Gbps to 100 m, Cat 6 supports 10 Gbps only to about 55 m, and Cat 6a supports 10 Gbps to 100 m. Plenum-rated jackets are required in air-handling spaces. Single-mode fiber reaches much farther than multimode. VGA is analog; HDMI, DisplayPort and most DVI are digital. USB 2.0 runs at 480 Mbps and USB 3.0 at 5 Gbps.
- How it shows up
- A cable run passes through a drop ceiling used for air return, spans a long distance, or needs 10 Gbps, and you choose the cable and rating.
- Common confusion
- Assuming Cat 6 gives 10 Gbps at full 100 m length. That requires Cat 6a.
3.3 Compare and contrast RAM characteristicsDIMM vs. SODIMM, DDR generations, ECC and channel configurations.
- What it means
- Covers memory form factors (DIMM for desktops, SODIMM for laptops), DDR generations, error-correcting code (ECC) versus non-ECC, and single-, dual-, triple- and quad-channel configurations.
- What to understand
- DDR generations are keyed differently and are not interchangeable. ECC detects and corrects single-bit errors and needs a motherboard and CPU that support it, which is why it is common in servers. Multichannel memory raises bandwidth only when modules are installed in matched sets in the slots the board manual specifies.
- How it shows up
- A workstation upgrade or a server build states its board and needs, and you pick memory type, ECC and slot population.
- Common confusion
- Thinking ECC simply means faster or better memory. ECC adds error correction and must be supported by the platform.
3.4 Compare and contrast storage devicesHDDs, SSDs and their interfaces, RAID levels, and removable media.
- What it means
- Covers hard drives (spindle speeds of 5,400, 7,200, 10,000 and 15,000 rpm; 2.5- and 3.5-inch form factors), SSD interfaces (NVMe, SATA, PCIe, SAS) and form factors (M.2, mSATA), RAID 0, 1, 5, 6 and 10, and removable storage such as flash drives, memory cards and optical drives.
- What to understand
- M.2 is a form factor that may carry SATA or NVMe; NVMe over PCIe is far faster than SATA's 6 Gbps limit, and a slot may support only one of them. RAID 0 stripes for speed with no redundancy (minimum 2 drives), RAID 1 mirrors (2), RAID 5 stripes with single parity and survives one failure (3), RAID 6 uses dual parity and survives two (4), and RAID 10 stripes across mirrors (4).
- How it shows up
- A server needs a certain fault tolerance or a laptop needs a faster drive, and you choose the RAID level or SSD interface.
- Common confusion
- Thinking RAID is a backup. RAID keeps a system running through a drive failure, but deletions, corruption and ransomware are copied across the array.
3.5 Given a scenario, install and configure motherboards, central processing units (CPUs), and add-on cardsForm factors, connectors, sockets, firmware settings, cooling and expansion cards.
- What it means
- Covers ATX, microATX and ITX boards, PCI, PCIe, SATA, eSATA, M.2 and header connectors, AMD and Intel sockets and multisocket boards, BIOS/UEFI settings (boot order, USB permissions, TPM, fan control, Secure Boot, boot and BIOS passwords, temperature monitoring, virtualization support), encryption hardware (TPM, HSM), x86/x64 and ARM architectures, core configurations, expansion cards and cooling.
- What to understand
- CPU and board must share a socket and chipset. Secure Boot requires UEFI and blocks unsigned boot loaders; TPM stores keys for BitLocker and is required by Windows 11. Virtualization extensions (Intel VT-x, AMD-V) must be enabled in firmware for hypervisors. Thermal paste is applied thinly between CPU and heat sink, and a missing or dried layer causes overheating.
- How it shows up
- A hypervisor will not start, Windows 11 setup fails its checks, or a new CPU does not fit, and you choose the firmware setting or compatible part.
- Common confusion
- Confusing TPM and HSM. A TPM is a chip on one system's board; an HSM is a dedicated, often network-attached device that protects keys for many systems.
3.6 Given a scenario, install the appropriate power supplyInput voltage, output rails, connectors, wattage, modularity and redundancy.
- What it means
- Covers input voltage (110-120 VAC versus 220-240 VAC), output voltages (3.3 V, 5 V, 12 V), the 20+4-pin motherboard connector, redundant and modular supplies, wattage rating and energy efficiency.
- What to understand
- Size the supply to the total load with headroom, paying most attention to the 12 V rail that feeds the CPU and graphics card. Most modern supplies auto-switch input voltage; older ones have a manual selector that must match local mains. Modular supplies let you attach only needed cables to improve airflow, and redundant supplies keep servers running if one unit fails.
- How it shows up
- A new graphics card causes shutdowns under load, or a server must tolerate a power supply failure, and you choose wattage, connectors or redundancy.
- Common confusion
- Equating higher efficiency rating with higher wattage. Efficiency describes how little power is wasted as heat, not how much the supply can deliver.
3.7 Given a scenario, deploy and configure multifunction devices/printers and settingsSetup, drivers, connectivity, sharing, print settings, security and scanning.
- What it means
- Covers unboxing and siting a device, OS-appropriate drivers (PCL versus PostScript), firmware, USB, Ethernet and wireless connections, shared printers and print servers, duplex, orientation, tray and quality settings, security (user authentication, badging, audit logs, secured prints) and scanning to email, SMB folder or cloud with an ADF or flatbed.
- What to understand
- PCL is fast and widely supported for office printing, while PostScript describes pages device-independently and is preferred for graphics and design work. A print server centralizes queues, drivers and permissions. Secured or badge-release printing holds a job until the user authenticates at the device, which keeps confidential output from sitting in the tray.
- How it shows up
- An HR department needs confidential prints protected, or a scan-to-folder workflow fails, and you choose the setting or feature.
- Common confusion
- Assuming any driver for the printer model works. The driver must match the OS and the page description language the workflow needs.
3.8 Given a scenario, perform appropriate printer maintenanceMaintenance tasks for laser, inkjet, thermal and impact printers.
- What it means
- Covers laser printers (replace toner, apply a maintenance kit, calibrate, clean), inkjet (replace cartridges, clean printheads, calibrate, clear jams), thermal (replace heat-sensitive paper, clean the heating element, remove debris) and impact printers (replace ribbon, printhead and paper).
- What to understand
- A laser maintenance kit replaces wear parts such as the fuser and rollers at a page-count interval, after which the counter is reset. Inkjet head cleaning uses ink, so run it when output shows streaks or gaps rather than routinely. Thermal printers have no ink or toner; the heating element is cleaned with isopropyl alcohol. Impact printers are used for multipart forms.
- How it shows up
- A printer displays a maintenance message or produces a specific defect, and you choose the task that matches its technology.
- Common confusion
- Ordering ink or ribbon for a direct thermal printer. It uses heat-sensitive paper and has no other consumable.
High-yield concepts
The terms, rules and formulas this domain turns into questions most often.
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RAID levels
RAID 0 striping, RAID 1 mirroring, RAID 5 striping with single parity, RAID 6 striping with dual parity, RAID 10 a stripe of mirrors.
- Remember
- Minimum drives are 2, 2, 3, 4 and 4; fault tolerance is none, one drive, one drive, any two drives, and one per mirror.
- Tested as
- Asked whenever a server, NAS or workstation needs speed or redundancy.
- Trap
- Picking RAID 0 for safety because it uses multiple drives, when it fails completely if any drive fails.
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M.2, NVMe and SATA
M.2 is a small card form factor; NVMe is a protocol over PCIe lanes; SATA is an older interface capped at 6 Gbps.
- Remember
- An M.2 drive can be SATA or NVMe, and a given slot may support only one, so check the board manual.
- Tested as
- Upgrade scenarios where the new drive is not detected.
- Trap
- Assuming every M.2 SSD is NVMe and fast.
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Cat 5e, Cat 6 and Cat 6a
Twisted-pair categories with increasing performance.
- Remember
- Cat 5e reaches 1 Gbps at 100 m, Cat 6 reaches 10 Gbps only to about 55 m, and Cat 6a reaches 10 Gbps at 100 m.
- Tested as
- Cable selection for speed and distance.
- Trap
- Choosing Cat 6 for a 90 m 10 Gbps run.
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Plenum and direct burial
Plenum cable has a fire-resistant, low-smoke jacket for air-handling spaces; direct burial cable is built for underground runs without conduit.
- Remember
- Building codes require plenum-rated cable in spaces used for air circulation, such as many drop ceilings.
- Tested as
- Installation scenarios that mention ceilings, HVAC or outdoor trenches.
- Trap
- Choosing standard PVC cable for an air-return ceiling because it is cheaper.
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Single-mode vs. multimode fiber
Single-mode uses a narrow core and laser light for long distances; multimode uses a wider core for shorter runs.
- Remember
- Single-mode spans kilometers between buildings or campuses; multimode suits runs within a building.
- Tested as
- Long-distance link selection.
- Trap
- Choosing multimode for a multi-kilometer link because it sounds more capable.
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T568A vs. T568B
Two pin-and-color standards for terminating RJ45 connectors; they swap the green and orange pairs.
- Remember
- Use the same standard on both ends for a straight-through cable; using A on one end and B on the other makes a crossover.
- Tested as
- Cable-making and pinout scenarios.
- Trap
- Thinking A and B differ in speed; only the pair positions differ.
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ECC memory
Memory with extra bits that detect and correct single-bit errors.
- Remember
- It requires motherboard and CPU support and is standard in servers.
- Tested as
- Server and workstation memory selection.
- Trap
- Installing ECC in a consumer board that does not support it and expecting it to work as ECC.
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Dual-channel memory
Two memory channels accessed in parallel to increase bandwidth.
- Remember
- Install matched modules in the color-coded or manual-specified slots; one module runs single-channel.
- Tested as
- Upgrade questions on getting full performance.
- Trap
- Placing two modules in adjacent slots on the same channel.
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TPM and Secure Boot
A Trusted Platform Module stores cryptographic keys in hardware; Secure Boot lets UEFI load only signed boot loaders.
- Remember
- Windows 11 requires TPM 2.0 and UEFI with Secure Boot capability; BitLocker uses the TPM.
- Tested as
- Windows 11 upgrade checks and disk encryption scenarios.
- Trap
- Looking for a software fix when the TPM is simply disabled in firmware.
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Virtualization support in firmware
CPU extensions such as Intel VT-x and AMD-V that hypervisors need.
- Remember
- They are often disabled by default and must be enabled in BIOS/UEFI.
- Tested as
- A hypervisor reports that virtualization is unavailable.
- Trap
- Reinstalling the hypervisor instead of changing the firmware setting.
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Power supply rails and wattage
Supplies convert AC mains to 3.3 V, 5 V and 12 V DC; wattage is the maximum continuous output.
- Remember
- The 12 V rail feeds the CPU and graphics card, so it matters most when adding a GPU.
- Tested as
- Shutdowns under load after an upgrade.
- Trap
- Choosing a supply by efficiency label alone without checking total wattage.
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PCL vs. PostScript
Two page description languages used by printer drivers.
- Remember
- PCL is common for general office output; PostScript gives device-independent, accurate graphics and fonts.
- Tested as
- Driver selection for design or publishing work.
- Trap
- Assuming the driver type does not affect output fidelity.
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Laser maintenance kit
A set of wear parts, typically the fuser assembly and rollers, replaced at a manufacturer page count.
- Remember
- Let the fuser cool before replacing it and reset the maintenance counter afterward.
- Tested as
- A laser printer shows a perform-maintenance message.
- Trap
- Replacing only the toner when the message refers to the maintenance interval.
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Display panel types
IPS for color and viewing angles, TN for fast response at low cost, VA for contrast; OLED is self-emissive.
- Remember
- OLED offers true blacks but risks burn-in from static images.
- Tested as
- Choosing a monitor for design, gaming or signage.
- Trap
- Recommending OLED for a kiosk that shows the same image all day.
Side by side
Concepts candidates mix up, compared on the point that decides the answer.
RAID 0 vs. RAID 1 vs. RAID 5 vs. RAID 6 vs. RAID 10
| Concept | Meaning | Key difference | Common trap |
|---|---|---|---|
| RAID 0 | Striping across at least 2 drives. | Fastest, full capacity, no fault tolerance. | Choosing it for important data. |
| RAID 1 | Mirroring across 2 drives. | Survives one failure; 50% usable capacity. | Thinking it protects against accidental deletion. |
| RAID 5 | Striping with distributed single parity, at least 3 drives. | Survives one failure; loses one drive's capacity. | Choosing it when two simultaneous failures must be survived. |
| RAID 6 | Striping with dual parity, at least 4 drives. | Survives any two failures; loses two drives' capacity. | Confusing its minimum drives with RAID 5. |
| RAID 10 | A stripe across mirrored pairs, at least 4 drives. | Fast and tolerant of one failure per mirror; 50% capacity. | Assuming it always survives any two failures. |
IPS vs. TN vs. VA vs. OLED
| Concept | Meaning | Key difference | Common trap |
|---|---|---|---|
| IPS | LCD with liquid crystals switching in plane. | Best color accuracy and viewing angles. | Choosing TN for color-critical design work. |
| TN | Twisted nematic LCD. | Fast response and low cost; color shifts at angles. | Recommending it where several people view from the side. |
| VA | Vertical alignment LCD. | High contrast and deep blacks for an LCD. | Assuming it matches IPS viewing angles. |
| OLED | Each pixel emits its own light; no backlight. | True blacks and thin panels; burn-in risk. | Using it for static signage. |
Laser vs. inkjet vs. thermal vs. impact maintenance
| Concept | Meaning | Key difference | Common trap |
|---|---|---|---|
| Laser | Toner fused to paper by heat and pressure. | Toner cartridge plus periodic maintenance kit. | Touching a hot fuser during service. |
| Inkjet | Liquid ink sprayed through printhead nozzles. | Cartridges, printhead cleaning and alignment. | Running head cleaning repeatedly and wasting ink. |
| Thermal | Heat darkens special paper. | Only paper is consumed; clean the heating element. | Ordering ribbon or toner. |
| Impact | Pins strike an inked ribbon against paper. | Ribbon, printhead and often tractor-feed or multipart paper. | Replacing it with a laser where carbon-copy forms are required. |
Exam traps
Each trap is an answer that looks right. Learn the clue that should change your mind.
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RAID as backup
- What candidates pick
- RAID 1 as the solution for recovering accidentally deleted files.
- Why it looks right
- Mirroring keeps a second copy of the data.
- Why it's wrong
- A mirror replicates deletions and corruption instantly; only a separate backup restores a previous state.
Clue to watch for The scenario mentions deleted, overwritten, encrypted or corrupted files rather than a failed drive.
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Cat 6 for long 10 Gbps runs
- What candidates pick
- Cat 6 for a 90 m run that must carry 10 Gbps.
- Why it looks right
- Cat 6 is commonly described as 10 Gbps cable.
- Why it's wrong
- Cat 6 supports 10 Gbps only to about 55 m; Cat 6a supports it to 100 m.
Clue to watch for Both a 10 Gbps requirement and a distance near 100 m.
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M.2 equals NVMe
- What candidates pick
- An M.2 SATA SSD for a slot that the board manual lists as PCIe NVMe only.
- Why it looks right
- The connector fits and the drive says M.2.
- Why it's wrong
- The slot does not support the SATA protocol, so the drive is not detected even though it fits physically.
Clue to watch for A newly installed M.2 drive does not appear in firmware or Disk Management.
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Software fix for a firmware setting
- What candidates pick
- Reinstall the hypervisor when it reports hardware virtualization is unavailable.
- Why it looks right
- The error appears inside the application.
- Why it's wrong
- VT-x or AMD-V must be enabled in BIOS/UEFI; reinstalling changes nothing.
Clue to watch for Error text about virtualization support or a new system with default firmware settings.
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Efficiency confused with capacity
- What candidates pick
- A higher-efficiency but lower-wattage power supply after adding a graphics card.
- Why it looks right
- Better efficiency sounds like a better supply.
- Why it's wrong
- Efficiency reduces wasted heat but does not add output; the system needs enough total and 12 V capacity.
Clue to watch for Shutdowns or reboots only under heavy graphics load.
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OLED for static content
- What candidates pick
- OLED panels for lobby signage that shows a fixed logo.
- Why it looks right
- OLED has the best contrast and image quality.
- Why it's wrong
- Static images can cause burn-in on OLED; an LCD type is safer for unchanging content.
Clue to watch for Displays that show the same image for long periods.
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Wrong consumable for the technology
- What candidates pick
- Replace the ribbon on a receipt printer that prints faded text.
- Why it looks right
- Faded output usually means a consumable is low.
- Why it's wrong
- Direct thermal receipt printers use heat-sensitive paper; clean the heating element or replace the paper, which may be loaded upside down or be the wrong type.
Clue to watch for The device is a receipt or label printer using thermal paper.
Answer framework
Use these steps for any hardware selection or installation question on Core 1.
- List every stated requirement, including capacity, speed, distance, fault tolerance, environment and budget, before reading the options, because most wrong answers satisfy all but one of them.
- Check physical compatibility: form factor, socket, slot keying, connector and DDR generation, using the motherboard or device manual as the authority.
- Check protocol or standard compatibility, such as NVMe versus SATA on M.2, Cat 6 versus Cat 6a, or PCL versus PostScript.
- Confirm firmware prerequisites like TPM, Secure Boot, virtualization extensions and boot order whenever software depends on hardware features, since many failures are a disabled setting rather than a bad part.
- Eliminate options that miss any single requirement, then choose the one meeting all of them with the least cost or complexity.
Practice question
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Study strategy
Work through this domain in the order a technician builds a PC: start with 3.5 (motherboards, CPUs and firmware), then 3.3 (RAM), 3.4 (storage and RAID) and 3.6 (power). Building or watching a full PC assembly once makes the connectors, slots and firmware settings concrete. Make a RAID table with minimum drives, usable capacity and fault tolerance and practice it until you can answer in seconds.
Next, cover 3.1 and 3.2 with comparison tables: panel types and display attributes, then cables grouped by job (network, peripheral, video, storage) with speed and distance limits. These two objectives are commonly underestimated because they look like simple recognition, yet many questions turn on a single detail such as Cat 6 distance or plenum rating.
Finish with 3.7 and 3.8 on printers. Learn the maintenance for each technology and the purpose of PCL, PostScript and secured printing. Afterwards, study Core 1 domain 5.0 objectives 5.1, 5.2 and 5.6, which test the same components as failure symptoms, and do timed practice sets that mix selection and troubleshooting questions.
FAQ
How much of Core 1 is the Hardware domain?
Hardware is 25% of Core 1 (220-1201), the second-largest Core 1 domain after Hardware and Network Troubleshooting at 28%.
Which RAID facts should I memorize?
For RAID 0, 1, 5, 6 and 10, know the minimum number of drives, how many failures each survives, and how much capacity is lost to redundancy. Also remember that RAID is not a backup.
Do I need to know every cable connector by sight?
You should recognize the connectors listed in objective 3.2, because questions and performance-based items may show or describe them. Focus on what each carries and where it is used.
Why is TPM in the hardware domain?
The TPM is a hardware chip enabled in firmware. Core 1 tests configuring it in BIOS/UEFI, while Core 2 tests the features that rely on it, such as BitLocker and the Windows 11 requirements.
Is there a printer process order to memorize for V15?
The V15 objectives focus on deploying multifunction devices and on maintenance tasks for laser, inkjet, thermal and impact printers. Understanding how a laser printer works still helps you match maintenance and symptoms to the right component.
What kind of questions should I expect?
Mostly selection scenarios with several constraints, identification by description, and maintenance tasks matched to printer technology. Read every requirement before eliminating options.
How does this domain connect to troubleshooting?
Core 1 domain 5.0 presents these components as failures, such as swollen capacitors, S.M.A.R.T. errors, a degraded array or ghosting on laser output. Knowing normal behavior here is what lets you diagnose those symptoms.
Other IT Fundamentals & Hardware certifications
Where the same subject shows up in other exams. Cards marked "Same subject" open the matching domain.
Test your Domain 3 knowledge
You have covered displays, cables, memory, storage and RAID, motherboards and firmware, power supplies and printers. Check whether you can meet every constraint in timed hardware selection questions.
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