A technician is troubleshooting a desktop computer that does not power on. The motherboard's power LED is lit. When the power button is pressed, no fans spin and no beeps occur. The technician uses a multimeter to test the power supply. The purple wire (+5VSB) reads 5.1V. The green wire (PS_ON) reads 0V when the power button is pressed. However, all other pins on the main power connector show 0V. Which of the following is the most likely cause?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
Distractor review
The motherboard is faulty.
The motherboard powers the LED with standby voltage and correctly pulls PS_ON low, so it is likely functioning correctly. A faulty motherboard would not generate the PS_ON signal.
Distractor review
The power button is defective.
The power button is part of the circuit that pulls PS_ON low. The fact that PS_ON goes to 0V when pressed indicates the button and its connection are working.
Best answer
The power supply unit is faulty.
The PSU is receiving the turn-on signal (PS_ON low) but is not producing the main DC voltages. This is a classic symptom of a failed PSU internal regulator or capacitor.
Distractor review
The CPU is not seated properly.
A misseated CPU would typically cause the system to power on (fans spin) but not POST or display video. It would not prevent the PSU from generating main voltages.
Common exam trap
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Technical deep dive
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A user reports intermittent network connectivity on a desktop computer. The technician observes that the Ethernet link light on the NIC turns off for a few seconds and then turns back on. The cable passes a wiremap test, the switch port is verified good with another device, and the NIC driver is updated. The issue occurs more frequently when the computer's case fan runs at high speed. Which of the following is the MOST likely cause?
Question 2
A workstation is unable to connect to the internet. The technician runs the 'ipconfig' command and sees the IPv4 address is 169.254.15.200 with a subnet mask of 255.255.0.0. The workstation can ping other devices on the local subnet but cannot ping the default gateway or any external addresses. Which TWO actions should the technician take to resolve this issue? (Select two.)
Question 3
A workstation is connected to a managed switch. It obtains a valid IP address (192.168.10.50) from the DHCP server, but it cannot ping the default gateway (192.168.10.1). The link light on both the workstation NIC and the switch port are solid green. Other workstations on the same switch CAN ping the default gateway successfully. The technician accesses the switch management interface and finds that the workstation's port is configured as an access port on VLAN 10. The default gateway is located on VLAN 20. An inter-VLAN router is configured but not explicitly allowing VLAN 10 access to VLAN 20. Which of the following is the MOST likely cause of the problem?
Question 4
A company develops a web application that relies on a custom library available only for a specific Linux distribution. They want to deploy the application in the cloud with minimal administrative overhead, but they need full control over the software stack, including the ability to install the custom library and configure the web server. Which cloud service model BEST meets these requirements?
Question 5
A company has a legacy virtual machine running on a deprecated hypervisor (Hyper-V). They want to migrate this VM to a new hypervisor (VMware vSphere) hosted in a private cloud while preserving the VM's configuration, installed applications, and data. The migration must be performed with minimal downtime. Which of the following methods is MOST appropriate?
Question 6
A company hosts a critical database on a virtual machine in a public cloud. The database requires persistent storage that must be retained even if the VM is terminated. The storage must also be accessible from multiple VMs simultaneously for a future high-availability configuration. Which type of cloud storage BEST meets these requirements?
FAQ
Questions learners often ask
What does this 220-1101 question test?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: The power supply unit is faulty. — The +5VSB (standby voltage) is present, indicating the power supply is receiving AC power. The PS_ON signal going low (0V) means the motherboard is correctly sending the 'power on' signal. However, the power supply is not generating the main voltages (+12V, +5V, +3.3V), which points to an internal failure of the power supply unit (PSU).
What should I do if I get this 220-1101 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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