rigvelaPC won’t turn on: no response to the power button
Quick answer
First check the mains lead, outlet or strip, and PSU switch. Disconnect mains power before inspecting internal connections. A stationary PSU fan alone does not identify a faulty power supply.
Fans run, but there is no display →Pressing the button does not start the PC? Begin with power outside the case. If fans already run but the screen stays blank, use the no-display checks instead. This guide is for a desktop PC; use the manufacturer’s instructions for a laptop or proprietary system.
Checklist as text
You can select and copy this text manually. The list does not mark any checks as completed.
On this page
Choose a check from the symptom
Note what happens after one press: no response, a motherboard light, or a start that stops immediately. A lit indicator does not confirm POST, and a still PSU fan alone does not prove a failure.
| Observation | Next check |
|---|---|
| No response to the button | Check the external power path, then internal connections.Go to this check → |
| Board lights are on, but the button does nothing | Verify the case-button connection; lighting does not replace this check.Go to this check → |
| Brief start, shutdown or a stationary PSU fan | Do not diagnose from one sign. Record the behaviour and check the limitations below.Go to this check → |
Check power outside the case
Inspect the mains lead and its connection at the PSU. Check the power-strip switch and the PSU’s rear switch; the on position is usually marked I. If the lead and outlet are undamaged, rule out the strip using a suitable known-working outlet.
Stop for smoke, a burning smell, a damaged lead or a tripping protection device. Disconnect power if safe and seek help. Do not open the PSU or insert objects through its grille.
Verify motherboard and CPU power
Before opening the case, switch off the PSU and unplug its mains lead. Use the board and PSU manuals to identify main ATX and CPU power. Check seating and the connections your board requires; “one 8-pin is always enough” is not universal.
A CPU/EPS 4+4 cable and a GPU PCIe 6+2 cable are not interchangeable. Do not force a plug. Use the modular PSU’s supplied cables or ones explicitly confirmed compatible by its manufacturer; a fitting connector does not establish the pinout.
Locate the case-button connection
With mains power disconnected, find the front-panel header and Power Switch / PWR SW contacts in the board manual. MSI calls the header JFP1 in the linked instructions; your board’s name, position and layout may differ.
Verify that the case-button lead reaches the right contacts, rather than a power LED or Reset connection. Do not copy another board’s photo or bridge unidentified pins. If you cannot confidently read the layout, ask the manufacturer for help.
Do not judge PSU health from its fan
Some PSUs have Zero RPM operation: the fan can remain stopped until cooling is needed. Check your exact PSU’s manual. This is not a health test, and neither is a brief twitch during a start attempt.
If the PC immediately shuts down or these checks do not help, avoid endless start attempts. Have a technician check with a known-good PSU; a modular replacement also requires its correct cable set. A wattage calculator cannot identify the failed component.
Record the details for the next check
Record whether the PC worked before and what changed before the problem. Support will need exact board and PSU models, connected cables and the response to the button. Photograph only accessible connections with power disconnected.
Quick checklist
- Full motherboard, CPU and PSU model names recorded.
- Changes immediately before the problem noted.
- External power, ATX/EPS and PWR SW checked separately.
- Further attempts stopped if damage is suspected.
Record the models for the next check
After the power checks, enter the exact board, CPU and PSU models. Use the list to open their documentation and describe the setup to support. Compatibility checking cannot diagnose a faulty PSU or other component.
Documentation & sources
These are the documents used in this guide. Check your exact model’s specifications on its support page.