Power Supply

Standard voltage range for most residential and commercial power outlets in the United States

110-120 VAC

Standard voltage range used for power outlets in Europe

220-240 VAC

A PSU's operation can be adjusted to the supplied voltage either by using a manual voltage selector on the back of the unit or automatically by the device. PSUs equipped with a manual voltage selector are referred to as fixed-input devices, while PSUs offering automatic voltage adjustment are known as auto-switching PSUs. (T/F)

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DC

Type of electric current is supplied to most of the internal PC components

PC components that use circuits that operate at voltages up to 3.3V?

NVMe M.2 slots

RAM slots

PC components that operate on the 5V voltage rail?

USB ports and devices

PC components that typically draw power from the 12V voltage rail provided by the power supply

Mechanical parts (e.g., case fans, motors, actuators)

Graphics cards

PCIe expansion cards

Modern ATX motherboards use a 24-pin power connector. Some power supplies feature a 20+4-pin connector to maintain compatibility with both 20-pin and 24-pin motherboards. The 20+4 connector can be used fully assembled for 24-pin motherboards or with the 4-pin section left unattached for 20-pin motherboards. (T/F)

True

Redundant Power Supply

Required for a load-balancing setup where supplied power is split between multiple PSUs that automatically share the load and provide backup in case of a PSU failure

In a modular power supply, the cables can be detached and reattached as needed, providing the flexibility to only use the cables required for the system, which helps reduce cable clutter and promotes better airflow within the computer case. (T/F)

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Watt

Power output rating of a PSU is measured in this unit

When selecting a PSU with energy efficiency in mind, the most important factor to consider is the 80 PLUS certification. This program rates PSUs based on their efficiency at various load levels, ensuring that they meet a minimum efficiency threshold. To maximize energy efficiency, reduce wasted energy, and lower long-term electricity costs, it is advisable to choose a PSU with a higher 80 PLUS rating, such as Gold, Platinum, or Titanium. These certifications indicate that the PSU operates more efficiently, reducing both energy loss and operational costs. (T/F)

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