Part of the Best 10 Singapore Glossary › Tech & Gadgets › PSU
A PSU (Power Supply Unit) is the component that converts mains electricity from your wall socket into the stable, low-voltage power your PC’s parts need. It’s one of the most overlooked parts of a computer — until it fails and the whole system won’t turn on. A failing or underpowered PSU is a common cause of no-boot, random shutdowns, and instability.
Key Things to Know
| Factor | What It Means |
|---|---|
| Wattage | Total power it can deliver — must exceed your system’s draw |
| 80 PLUS rating | Efficiency tier (Bronze, Gold, Platinum) — higher wastes less |
| Modularity | Detachable cables for tidier builds |
| Brand quality | No-name units can fail and damage other parts |
⚠️ Warning: A cheap or failing PSU can take other components down with it. If your PC won’t power on or shuts down at random, the PSU is one of the first things a technician will test.
Signs of a Failing PSU
PC won’t turn on at all · Random shutdowns or restarts under load · Burning smell or buzzing from the unit · Fans spin briefly then stop · System instability that isn’t fixed by other component swaps.
Related Glossary Terms
What is a GPU? →
What is a CPU? →
What is Thermal Paste? →
What is Chip-Level Repair? →
🖥️ Need a PSU replaced? See our guide to the Best PC Repair Services in Singapore →