# PSU

CEFR C1 · Noun

Source: https://englishreference.com/word/psu
Updated: 2026-07-22

## Definition

Stands for Power Supply Unit. The part of a computer or electronic device that takes electricity from the wall and changes it into the right type of power for the machine.

For teachers: Abbreviation for Power Supply Unit. A hardware component that converts mains alternating current (AC) into low-voltage regulated direct current (DC) power for the internal components of a computer or electronic system.

## Examples

- The computer won't turn on because the PSU is broken.
- When building a high-end gaming PC, you must ensure the PSU has enough wattage to support the graphics card and processor.
- A high-quality PSU not only provides stable voltage to sensitive components but also includes protections against power surges and short circuits that could otherwise lead to catastrophic hardware failure.

## Usage notes

- Typically used in technical or enthusiast contexts regarding computer hardware and electronics.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.