Power Supply — CompTIA A+ Core 1 (220-1101) Practice Questions
The power supply unit (PSU) converts AC power from a wall outlet into the regulated DC voltages that computer components require, and it is a frequently tested topic on the CompTIA A+ Core 1 exam. Key knowledge areas include voltage rails (3.3 V, 5 V, 12 V), wattage capacity planning, connector types (24-pin ATX, PCIe 6/8-pin, SATA, Molex), and efficiency ratings under the 80 Plus standard. Technicians must know how to select an appropriately rated PSU for a given system build, test output voltages during troubleshooting, and recognize symptoms of PSU failure such as random shutdowns or failure to POST. The PSU is often overlooked as a failure point, making this knowledge especially valuable in the field.
Free questions on power supply
What is the standard voltage for AC power in the United States?
Free question · easy · full answer + explanation
More power supply questions in the full bank
- A technician is installing a new high-performance GPU in a workstation. The system currently has a 400W power supply. What is the most important consideration before installation? Unlock answer & explanation →
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