CompTIA A+ Core 1 220-1101 practice test

A technician is assembling a new desktop computer with an AMD Ryzen 5 CPU on a B550 motherboard. After installing the CPU, heatsink, RAM, and graphics card, and connecting all power cables, the technician powers on the system. The case fans spin, the motherboard LEDs light up, but there is no display output and no beep codes. The motherboard has a set of diagnostic LEDs; the LED labeled 'CPU' remains lit. Which of the following should the technician check FIRST?

Trap 1: Reseat the RAM modules and try different slots

A RAM issue usually triggers a DRAM diagnostic LED or specific beep codes, not a CPU LED. The CPU LED points specifically to a problem with the CPU itself or its power delivery.

Trap 2: Reinstall the dedicated graphics card

A graphics card issue would typically cause no video output but would not illuminate the CPU LED. The LED indicates a CPU-related problem.

Trap 3: Update the motherboard BIOS to support the CPU

BIOS incompatibility could cause a CPU error, but it is less common than a missing power cable and should be investigated only after verifying all physical power connections are secure.

A
Reseat the RAM modules and try different slots
Why wrong: A RAM issue usually triggers a DRAM diagnostic LED or specific beep codes, not a CPU LED. The CPU LED points specifically to a problem with the CPU itself or its power delivery.
B
Verify that the 8-pin CPU power cable is connected to the motherboard
The CPU power connector (often 4+4 pin) must be connected for the processor to receive power. If missing, the motherboard will show a CPU error LED.
C
Reinstall the dedicated graphics card
Why wrong: A graphics card issue would typically cause no video output but would not illuminate the CPU LED. The LED indicates a CPU-related problem.
D
Update the motherboard BIOS to support the CPU
Why wrong: BIOS incompatibility could cause a CPU error, but it is less common than a missing power cable and should be investigated only after verifying all physical power connections are secure.

Question 2mediummultiple choice

A technician is building a desktop computer and applies thermal paste to the CPU before installing the heatsink. The technician uses significantly more paste than recommended. Which of the following is the most likely consequence of this action?

Trap 1: The thermal paste will cause a short circuit on the motherboard

Most modern thermal pastes are non-conductive, so a short circuit is unlikely unless conductive (silver-based) paste is used, but even then spillover is the greater risk, not the primary consequence.

Trap 2: The CPU will run cooler due to better coverage

This is incorrect because excess paste actually hinders thermal transfer; a thin, even layer is optimal for conduction.

Trap 3: There will be no noticeable effect on system performance

Excess paste can significantly impact thermals and may cause instability or reduced performance due to thermal throttling.

A
The CPU will overheat because excess paste reduces heat transfer efficiency
Too much paste creates a thick layer that impedes heat transfer from the CPU to the heatsink, leading to higher temperatures and potential thermal throttling or damage.
B
The thermal paste will cause a short circuit on the motherboard
Why wrong: Most modern thermal pastes are non-conductive, so a short circuit is unlikely unless conductive (silver-based) paste is used, but even then spillover is the greater risk, not the primary consequence.
C
The CPU will run cooler due to better coverage
Why wrong: This is incorrect because excess paste actually hinders thermal transfer; a thin, even layer is optimal for conduction.
D
There will be no noticeable effect on system performance
Why wrong: Excess paste can significantly impact thermals and may cause instability or reduced performance due to thermal throttling.

Question 3hardmultiple choice

A technician is building a custom workstation for 3D rendering. The components include an AMD Ryzen 7 5800X CPU, a B550 motherboard (box states 'AMD Ryzen 3000 desktop ready'), two 16GB DDR4-3600 modules (on the QVL), and a dedicated GPU. The system powers on, case fans spin, and the CPU fan spins, but the motherboard’s CPU debug LED remains lit and there is no display. The technician has reseated the CPU and found no bent pins. The RAM and GPU have been verified working in another system. The PSU is a known-good 750W unit. Which of the following should the technician do NEXT?

Trap 1: Replace the power supply with a higher-wattage unit

The system powers on and fans spin, indicating the PSU is delivering enough power. A higher wattage PSU would not resolve a CPU recognition issue indicated by the CPU debug LED.

Trap 2: Test the system with a known-working Ryzen 3000 CPU

While this would confirm whether the CPU is incompatible, it is often not the most practical first step because a technician may not have a spare CPU. A BIOS update is usually easier and faster to perform.

Trap 3: Replace the motherboard with a newer model that officially supports…

Replacing the motherboard is expensive and unnecessary if a BIOS update can resolve the compatibility issue. It should be considered only after updating the BIOS proves unsuccessful.

A
Replace the power supply with a higher-wattage unit
Why wrong: The system powers on and fans spin, indicating the PSU is delivering enough power. A higher wattage PSU would not resolve a CPU recognition issue indicated by the CPU debug LED.
B
Upgrade the motherboard BIOS using the BIOS flashback feature
The motherboard likely has an older BIOS that does not support the Ryzen 5000 series CPU. Updating the BIOS to the latest version may enable compatibility and allow the system to POST. Many B550 boards can be updated without a CPU using a USB flash drive and a dedicated button.
C
Test the system with a known-working Ryzen 3000 CPU
Why wrong: While this would confirm whether the CPU is incompatible, it is often not the most practical first step because a technician may not have a spare CPU. A BIOS update is usually easier and faster to perform.
D
Replace the motherboard with a newer model that officially supports Ryzen 5000
Why wrong: Replacing the motherboard is expensive and unnecessary if a BIOS update can resolve the compatibility issue. It should be considered only after updating the BIOS proves unsuccessful.

Read the full NAT/PAT explanation →

Question 4mediummultiple choice

A technician installs a new M.2 SATA SSD into a desktop motherboard. The SSD is not detected in the BIOS. The technician has verified that the SSD is compatible with the motherboard and that it is fully seated. Which of the following is the MOST likely cause?

Trap 1: The SSD needs to be formatted

Unformatted drives are still detected by the BIOS. Formatting is an operating system step, not a BIOS detection issue.

Trap 2: The BIOS does not support SATA SSDs

Most modern BIOS versions support SATA SSDs in M.2 form factor. This is unlikely.

Trap 3: The motherboard requires a firmware update

While a firmware update could resolve compatibility issues, the more common and immediate cause is the shared SATA port configuration.

A
The M.2 slot shares bandwidth with a SATA port that is in use
This is a common design; check the motherboard manual to see which SATA ports are disabled when an M.2 SATA drive is installed.
B
The SSD needs to be formatted
Why wrong: Unformatted drives are still detected by the BIOS. Formatting is an operating system step, not a BIOS detection issue.
C
The BIOS does not support SATA SSDs
Why wrong: Most modern BIOS versions support SATA SSDs in M.2 form factor. This is unlikely.
D
The motherboard requires a firmware update
Why wrong: While a firmware update could resolve compatibility issues, the more common and immediate cause is the shared SATA port configuration.

Question 5mediummultiple choice

A small business wants to migrate its internal applications to the cloud to reduce hardware maintenance costs. They wish to retain control over the application code and configuration but do not want to manage the underlying operating system or runtime environment. Which cloud service model BEST meets their needs?

Trap 1: Software as a Service (SaaS)

SaaS provides ready-to-use applications managed entirely by the provider. Customers do not control the application code or configuration, which contradicts the requirement.

Trap 2: Infrastructure as a Service (IaaS)

IaaS provides virtualized computing resources such as VMs, storage, and networking. Customers are responsible for managing the OS, runtime, and applications, which would still require OS management, contradicting the requirement.

Trap 3: Desktop as a Service (DaaS)

DaaS delivers virtual desktop environments to end users. It is designed for desktop virtualization, not for hosting custom applications while abstracting OS management.

A
Software as a Service (SaaS)
Why wrong: SaaS provides ready-to-use applications managed entirely by the provider. Customers do not control the application code or configuration, which contradicts the requirement.
B
Platform as a Service (PaaS)
PaaS offers a development and deployment environment where the provider manages the infrastructure, OS, and middleware, but the customer manages the applications and data. This aligns perfectly with the described needs.
C
Infrastructure as a Service (IaaS)
Why wrong: IaaS provides virtualized computing resources such as VMs, storage, and networking. Customers are responsible for managing the OS, runtime, and applications, which would still require OS management, contradicting the requirement.
D
Desktop as a Service (DaaS)
Why wrong: DaaS delivers virtual desktop environments to end users. It is designed for desktop virtualization, not for hosting custom applications while abstracting OS management.

Question 6easymultiple choice

A technician replaced the screen assembly on a smartphone. After reassembly, the phone powers on and displays correctly, but the touch screen is unresponsive. Which of the following should the technician check FIRST?

Trap 1: Reboot the phone into safe mode

Safe mode disables third-party apps but does not affect hardware connections; if the digitizer is unseated, safe mode will not fix it.

Trap 2: Update the touch screen drivers

Drivers are part of the operating system; a hardware connection issue must be resolved first, and driver updates rarely fix a completely unresponsive touch after replacement.

Trap 3: Replace the screen assembly again

Replacing the assembly again is premature. First rule out a simple connection issue, which is more common and less costly.

A
Reboot the phone into safe mode
Why wrong: Safe mode disables third-party apps but does not affect hardware connections; if the digitizer is unseated, safe mode will not fix it.
B
Update the touch screen drivers
Why wrong: Drivers are part of the operating system; a hardware connection issue must be resolved first, and driver updates rarely fix a completely unresponsive touch after replacement.
C
Ensure the digitizer ribbon cable is properly seated
The digitizer cable is often separate from the display cable; if it is loose or not fully inserted, the touch input will not work.
D
Replace the screen assembly again
Why wrong: Replacing the assembly again is premature. First rule out a simple connection issue, which is more common and less costly.