A paperclip test can request startup from a compatible ATX PSU without a motherboard, but it cannot prove that the PSU supplies stable power under load. Use the manufacturer’s documented procedure and exact connector diagram; a purpose-made jumper is preferable to improvised exposed metal.
This guide concerns a supported standard motherboard-side 24-pin ATX cable. It does not apply to a proprietary OEM connector, the modular sockets on the PSU, a CPU power plug or an opened PSU enclosure.
Decide whether this is the right test
If a PC will not start, first check the wall supply, power cable, rear switch and visible system connections with power isolated. A disconnected front-panel switch or motherboard fault can resemble a failed PSU.
The paperclip test bypasses the motherboard’s normal power-on request. A successful startup narrows the investigation but leaves many possible PSU faults untested.
Do not perform it on a unit that smells burnt, has liquid contamination, visible damage or an unknown connector standard. Contact the manufacturer or a qualified repair service instead.
Never open a PSU enclosure. Internal capacitors can retain hazardous energy after the mains cable is removed. This test requires no access inside the casing.
Use the exact connector diagram
Corsair’s PSU test guide identifies pins 16 and 17 on its standard 24-pin motherboard-side connector. The orientation in the manufacturer’s image is essential; do not count from a remembered photograph or an unspecified viewing side.
The intended connection is PS_ON to ground on the documented connector. All-black cables make wire-colour shortcuts particularly unreliable. A compatible supplied jumper avoids some of the ambiguity.
Do not bridge a pair on an 8-pin CPU or graphics-power cable. Do not bridge the modular socket on the PSU itself. Modular PSU-side wiring is not a universal pinout, even when connectors look alike.
If the exact cable cannot be identified confidently, stop. A tester or support-guided diagnosis is a better next step than guessing which contact is correct.
Set up only with mains disconnected
Shut down the computer, switch off the PSU and unplug its mains cable before handling connections. Follow the manufacturer’s discharge and preparation instructions.
Disconnect the PSU outputs from the motherboard, GPU, drives and other system loads as directed by the test guide. For a modular unit, use only the cables intended for that exact PSU.
With no power connected, fit the approved jumper to the documented motherboard-side 24-pin connector. Keep it secure, isolated from the chassis and away from any other contact.
Do not insert, adjust or remove a jumper while the PSU is powered. Never hold exposed jumper metal during the live portion of the test. If you cannot make the setup stable and clear, do not energise it.
Observe the model’s expected response
Reconnect mains and operate the switch only after the setup matches the manufacturer’s procedure and your hands are clear. Observe the expected startup behaviour without touching the connector.
A zero-RPM or semi-passive fan can briefly spin and stop, or follow another model-specific control pattern. A stationary fan is not automatically a failed PSU. Check the unit’s instructions before drawing a conclusion.
Equally, a spinning fan is not proof of correct voltage regulation, ripple performance, protection operation or adequate power at gaming load. Treat it as a startup observation.
If the PSU makes an abnormal sound, emits an odour or behaves unexpectedly, switch off and disconnect mains. Do not repeatedly cycle a suspect unit to force a different result.
Interpret a pass and a failure cautiously
A startup response suggests the unit can respond to the power-on request in that setup. It does not clear it of intermittent shutdowns, load-related failures or cable faults.
No expected response can be consistent with a fault, but also with a wrong setup or misunderstood fan mode. Recheck the instructions with mains disconnected; do not try different arbitrary pins.
A basic PSU tester can provide additional information, yet an unloaded reading still differs from a controlled load test. A multimeter also requires correct technique and does not measure every aspect of supply quality.
I would use manufacturer support or an appropriate technician for deeper electrical diagnosis. Swapping in a verified compatible known-good PSU can be useful when performed correctly, including changing to that PSU’s own cables.
Restore the system safely
Switch off and unplug mains before removing the jumper. Confirm it is completely removed and no exposed metal remains near the connector.
Reconnect only the correct cables and verify all required motherboard, CPU, GPU and drive connections. Our PC build checklist helps put power requirements back into the wider system context.
Document what the test actually showed. Write “responded to startup request” rather than “PSU proven healthy.” That wording prevents a limited test from ruling out the real cause too early.
If connector identity or the instructions remain uncertain, leave the unit disconnected and ask for help. A PSU is too consequential a component for trial-and-error pin bridging.