Use this method if your PC won't turn on at all (no lights, no fans) and you want to know if the power supply unit (PSU) is dead.
If your computer turns on but crashes under load (random restarts or blue screens), you can check voltages via software. Note that this is less accurate than a multimeter. check power supply pc
If readings are outside these ranges, your PSU is unstable and could be damaging your components. Use this method if your PC won't turn
Ultimately, checking a power supply is an exercise in holistic diagnosis. If a PSU fails any physical inspection, the paperclip test, or the multimeter check, it must be replaced. Even if it passes all tests but the system continues to exhibit classic power-failure symptoms, it is often prudent to swap the PSU with a known-good spare. Due to the PSU’s role as the gateway for all electricity, a failing unit does not merely stop working; it can catastrophically fail, sending a surge of voltage through the motherboard, CPU, and storage drives, destroying them instantly. If readings are outside these ranges, your PSU