📖 What is Power Supply Unit (PSU)?
The Power Supply Unit (PSU) converts AC power from the wall outlet into DC power usable by computer components. Wattage indicates the total power output, while efficiency ratings (80+ Bronze, Gold, Platinum) reflect energy conservation. Modular PSUs allow for selective cable connections.
"Pay close attention to wattage requirements based on system components, especially the GPU. Understand the importance of voltage selection (115V/230V) for international compatibility. The exam may include scenarios involving PSU failure diagnosis."
📚 Certification: CompTIA A+ Certification Exam Core 1 (220-1101)
🔑 What are the Key Concepts of Power Supply Unit (PSU)?
- ▸ Wattage is crucial; insufficient power prevents system boot or causes instability, especially with high-end GPUs and CPUs.
- ▸ Efficiency ratings (80+ Bronze, Gold, Platinum, Titanium) indicate how much power is delivered versus wasted as heat.
- ▸ Modular PSUs simplify cable management and improve airflow, but are not essential for system functionality.
- ▸ PSUs supply various DC voltages (+3.3V, +5V, +12V) required by different components; the +12V rail powers most components.
- ▸ Voltage selection switches (115V/230V) are vital for international use; incorrect setting can damage the PSU and connected hardware.
🎯 How does Power Supply Unit (PSU) appear on the 220-1101 Exam?
You may be asked to determine the minimum PSU wattage required for a system given the power draw of the CPU, GPU, and other components.
A scenario might describe a computer failing to boot after adding a new graphics card – identify the PSU as the likely cause if wattage is insufficient.
Expect questions about troubleshooting a system that randomly shuts down under load, potentially indicating a failing or inadequate PSU.
❓ Frequently Asked Questions
What does 80+ certification actually measure?
80+ certification measures PSU efficiency at different load levels (20%, 50%, 100%). Higher ratings mean less wasted energy and lower electricity bills, but also typically higher cost.
How do I determine the power draw of my components?
Check the manufacturer's specifications for each component (CPU, GPU, motherboard, etc.). They will list the typical and maximum power draw in watts. Add these up to estimate total system power needs.
Can a PSU failure damage other components?
Yes, a failing PSU can deliver unstable or incorrect voltages, potentially damaging sensitive components like the CPU, GPU, and motherboard. A surge protector is recommended, but doesn't prevent PSU failure.