CompTIA A+ guideCore 1 skills
A+ Core 1 Hardware: Cables, Connectors, RAM, Motherboards, and Power
Identify every connector on 220-1201 by the job it does, then work through RAM, motherboards, firmware settings, power supplies, and displays the way the exam asks.
Short answer
Hardware is 25% of 220-1201. Leaving out storage and printers, which have their own pages, it covers displays (3.1), cables and connectors (3.2), RAM (3.3), motherboards, CPUs, firmware settings, and add-on cards (3.5), and power supplies (3.6). Most questions come down to matching a part to its job: which connector carries what, which memory fits which computer, which firmware setting turns a feature on, and which power supply matches the outlet voltage and the system's wattage.
How Core 1 tests hardware
Hardware is 25% of Core 1, second only to Hardware and Network Troubleshooting at 28%, and the two domains feed each other: a symptom question often depends on knowing what a part does. Storage and RAID (3.4) are covered in the RAID and storage guide, and printers (3.7 and 3.8) in the printers guide. This page covers the rest.
Connectors: name it, then say what it carries
Objective 3.2 lists 13 connector types.
| Connector | What it is used for |
|---|---|
| RJ45 | Twisted-pair Ethernet |
| RJ11 | Telephone lines, including DSL service |
| F-type | Coaxial cable, as on a cable modem |
| ST | Fiber, with a bayonet twist-lock |
| SC | Fiber, with a square push-pull body |
| LC | Fiber, with a small latching body that fits dense switch ports |
| Punchdown block | Terminating twisted-pair runs in a wiring closet or patch area |
| MicroUSB and MiniUSB | Older phones, cameras, and small peripherals |
| USB-C | A reversible connector that can carry USB data, video, and power |
| Lightning | Older Apple phones and tablets |
| Molex | Four-pin internal power for older drives and fans |
| DB9 | Serial connections, such as console cables for network equipment |
Cables to pair with them. Copper network cable comes in categories and is wired to the T568A or T568B standard. Using the same standard on both ends gives a straight-through cable, while A on one end and B on the other gives a crossover. Shielded twisted pair resists interference, and direct burial cable is built to go underground. Plenum-rated cable has a jacket rated for the air-handling space above ceilings and under floors. Fiber is single-mode for long distances and multimode for shorter runs.
Video cables. HDMI and DisplayPort carry digital video and audio. DVI is an older video connector, and VGA is analog. USB-C can also carry video to a monitor that supports it. A question that mentions an old projector with a 15-pin blue connector is describing VGA.
Peripheral and drive cables. USB 2.0, USB 3.0, serial, and Thunderbolt connect peripherals. SATA connects internal drives, and eSATA was its external version.
RAM: what fits and what works together
| Concept from 3.3 | What to know |
|---|---|
| DIMM vs SODIMM | DIMMs go in desktops. SODIMMs are the smaller modules in laptops and small PCs. They are not interchangeable |
| DDR generations | Each DDR generation is keyed differently, so a module fits only boards built for that generation. A board supports one generation |
| ECC vs non-ECC | ECC memory detects and corrects some memory errors. It needs a board and CPU that support it, and is typical in servers and workstations |
| Channel configurations | Installing matched modules in the slots the board manual specifies lets the memory controller use more than one channel at once |
A typical scenario: a technician orders memory for a laptop and receives a desktop module. The answer is the form factor, SODIMM versus DIMM, before any speed or capacity detail.
Motherboards, CPUs, and firmware (3.5)
Form factors. ATX is the full-size desktop board, microATX is smaller, and ITX is smaller still. The case has to support the board's form factor.
Connectors on the board. Expect PCIe expansion slots (and legacy PCI), power connectors, SATA and eSATA ports, M.2 slots, and headers for front-panel buttons, USB, audio, and fans.
CPU compatibility. AMD and Intel use different sockets, and a board supports specific CPU models. Multisocket boards, mostly in servers, hold more than one CPU.
BIOS/UEFI settings.
| Setting | Why a technician changes it |
|---|---|
| Boot options | Change the boot order to start from USB or the network for an installation |
| USB permissions | Disable USB ports or USB booting on locked-down machines |
| TPM security features | Turn on the TPM that BitLocker and Windows 11 rely on |
| Secure Boot | Allow only trusted, signed boot software to load |
| Boot password | Require a password before the computer starts |
| BIOS password | Require a password before anyone changes firmware settings |
| Fan considerations and temperature monitoring | Adjust cooling and check temperatures when a system overheats |
| Virtualization support | Turn on the CPU's virtualization features so hypervisors can run |
Microsoft lists "UEFI, Secure Boot capable" and TPM version 2.0 among the Windows 11 hardware requirements, and says VM hosts running Hyper-V need virtualization (VT-x, VT-d) enabled in the BIOS. Those three settings show up in upgrade and virtualization questions. The virtualization guide covers the VM side.
Encryption hardware. A TPM is a security chip on or in the system board that stores keys and measures the startup process. Microsoft says BitLocker gives maximum protection when used with a TPM. A hardware security module (HSM) is a dedicated device or card that protects and manages keys, usually for servers and many systems at once.
CPU architecture and cards. x86/x64 is the architecture of most Windows desktops and laptops. ARM appears in phones, tablets, and a growing number of laptops. Core configuration means how many cores the CPU has, and expansion cards add sound, video, capture, or network capability. Cooling uses fans, heat sinks, thermal paste or pads between the CPU and heat sink, and sometimes liquid.
Power supplies (3.6)
| Topic | What to know |
|---|---|
| Input voltage | North American outlets supply 110–120 VAC, and many other regions use 220–240 VAC. Many supplies switch automatically. If one has a manual selector, it must match the outlet |
| Output voltages | 3.3 V, 5 V, and 12 V. Intel's ATX design guide shows +3.3 V, +5 V, +12 V, −12 V, and +5 V standby pins on the 24-pin main connector |
| 20+4 pin connector | A 24-pin main connector whose four-pin section separates for older 20-pin boards |
| Redundant power supply | Two supplies in one system, so it keeps running if one fails. Common in servers |
| Modular power supply | Cables detach, so you connect only the ones you need |
| Wattage rating | The supply must cover the total draw of the components, with headroom for upgrades |
| Energy efficiency | A more efficient supply wastes less power as heat |
A typical scenario: a user adds a powerful graphics card and the PC now shuts off under load. Check whether the power supply's wattage and connectors match the new card before blaming the card.
Displays (3.1)
| Display type or attribute | What to know |
|---|---|
| IPS (LCD) | Wide viewing angles and good color |
| TN (LCD) | Fast response, narrower viewing angles |
| VA (LCD) | Strong contrast, between IPS and TN on most other traits |
| OLED | Each pixel produces its own light, so there is no backlight. Static images can cause burn-in |
| Mini-LED | An LCD with many small LED backlight zones for better contrast |
| Touch screen and digitizer | The digitizer is the layer that senses touch or a stylus |
| Inverter | Powers the fluorescent backlight in older LCDs. A failed inverter gives a dim or dark image that is still faintly visible |
| Pixel density, refresh rate, resolution, color gamut | Sharpness, smoothness of motion, number of pixels, and the range of colors shown |
When a display fails, the symptoms in objective 5.3 apply, and the hardware and network troubleshooting guide walks through them.
Drill it on a real board
Open an old desktop with an ESD strap on and name every connector, slot, and cable you see. Then cover the right-hand column of each table and say the job from the name. When the tables feel easy, practice A+ Core 1 hardware questions with Passy, and keep a list of any connector you miss twice.
Trust the source
Official sources
Exam policies can change. Use these primary sources for the most current details.