Power Supply

5 minutes 5 Questions

A power supply unit (PSU) is an essential component of a computer system, responsible for converting the alternating current (AC) from a wall socket into the direct current (DC) required by the various components of the computer. The PSU ensures that each component receives the correct voltage and provides protection against power surges and short-circuits. It comes in various form factors and wattage capabilities to support different hardware configurations. When selecting a PSU, it's crucial to choose one with adequate power output and high efficiency to ensure a stable and energy-efficient system.

Guide to Power Supply in CompTIA A+ Exams

What is Power Supply?
A power supply is an internal hardware component of a computer system that supplies electric power to an electrical load. It's main function is to convert the alternating current (AC) from the wall socket into direct current (DC) to be used by the internal components of the computer.

Why is it important?
Understanding the power supply is fundamental because it is crucial for the functioning of a computer system. It's the primary source of power for a computer's many parts, so knowing how it works and troubleshooting related issues is key in the IT support field.

How does it work?
A computer power supply converts power from the wall socket and regulates it to the correct voltage for components such as the CPU, motherboard, and hard drives. Potential problems can arise from insufficient power supply, power surges or faulty power units.

Exam Tips: Answering Questions on Power Supply
When answering questions relating to the power supply in a CompTIA A+ exam, focus on understanding its functionalities, how to troubleshoot, and safety precautions. It's important to remember the difference between AC and DC and how the computer power supply manipulates these currents for the system's use. Also, remember to review different types of power supplies and the various connectors they may use.

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Question 1

A technician is diagnosing a PC that experiences intermittent shutdowns. What could be a possible reason for this issue?

Imbalanced CPU usage Faulty power supply Loose RAM Outdated graphics drivers

Correct Answer: Faulty power supply

A faulty power supply is the most likely cause of intermittent shutdowns in a PC. Power supply issues can cause the system to suddenly lose power and shut off unexpectedly. Loose RAM may cause system instability or boot failures, but it typically wouldn't lead to complete shutdowns. Imbalanced CPU usage or outdated graphics drivers might cause performance issues or crashes, but they are less likely to directly cause a PC to shut itself off intermittently compared to a failing power supply.

Question 2

A technician is troubleshooting a PC that produces a burning smell when turned on. When they open the case, they find no visible damage. What should be their next step?

Test the power supply for defects Inspect RAM for damage Reinstall the operating system Replace the graphics card

Correct Answer: Test the power supply for defects

Testing the power supply for defects is the best next step. A burning smell often indicates an issue with the power supply overheating or failing. Since no visible damage was found, systematically testing components is necessary. The power supply is the most likely culprit and should be checked first. Inspecting RAM, replacing the graphics card, or reinstalling the OS would not address the root cause of the burning smell, which is likely a hardware issue originating from the power supply.

Question 3

A user reports that their computer loses power every time they connect an external hard drive. What should a technician do to solve this problem?

Replace the power supply with a higher wattage unit Update the BIOS of the computer Defragment the computer's hard drive Disable the USB ports in the BIOS

Correct Answer: Replace the power supply with a higher wattage unit

The correct answer is: Replace the power supply with a higher wattage unit Explanation: If the computer loses power when connecting an external hard drive, it indicates that the power supply is not providing enough power to support the additional device. The power supply may be underpowered or failing. Replacing the power supply with a higher wattage unit will ensure that there is sufficient power to support the computer and any connected devices. The other options are incorrect: - Updating the BIOS would not address the power issue caused by an underpowered or failing power supply. - Defragmenting the computer's hard drive is unrelated to the power issue and would not solve the problem. - Disabling the USB ports in the BIOS would prevent the use of the external hard drive altogether, rather than solving the power issue.

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