Observation
Note whether there is any standby LED, click, or fan twitch at all.
PC no power
Use this flow when the PC does not turn on and shows no clear signs of life when the power button is pressed. The goal is to keep the next ask small before moving to minimum boot or component swap testing.
Safety first: stop immediately for smoke, sparks, liquid damage, or
visible power-supply damage. Never open a PSU.
What this flow is for
The system will not power on, and you still need to separate outlet or switch issues from cabling, front-panel wiring, case shorts, or hardware failure.
First safe checks
- Confirm the outlet, surge strip, and PSU switch before opening the case.
- Look for any motherboard standby LED or brief fan twitch when pressing power.
- Reseat the 24-pin and CPU 8-pin power leads.
- Verify the front-panel header or test the board's power pins carefully.
- Move to minimum boot only after the basic power path is confirmed.
Evidence requests
Ask for the smallest missing proof
Photo
Capture the 24-pin, CPU 8-pin, and front-panel header area.
Change log
List what changed most recently: case, PSU, motherboard, or cable swap.
Likely causes
Most likely problem buckets
Power path issue
Outlet, surge strip, or PSU switch is wrong or not supplying power.
Main power connection issue
24-pin, CPU 8-pin, or front-panel header is loose, missing, or miswired.
Case or switch fault
The board may be shorting in the case or the power switch path may be failing.
PSU or board failure
Hardware failure becomes more likely if minimum boot still shows no signs of life.
Next safe steps
Take one step at a time
ACT-PC-001
Confirm wall power, surge strip state, and the PSU switch position.
ACT-PC-002
Reseat the 24-pin and CPU 8-pin power leads, then check front-panel wiring.
ACT-PC-003
Record what changed most recently before swapping more parts.
ACT-PC-004
Run a minimum-boot test with CPU, cooler, one RAM stick, and known-good PSU if available.
Best follow-up ask
Do you see any standby LED or even a brief fan twitch when you press the power button?
When to stop and hand off
Escalate when minimum boot still shows no signs of life, or when you suspect PSU, board, or case-switch failure that now needs swap testing.
Support links
Keep the next step small
If the symptom changes from no power to lights, fans, or debug LEDs, move into the closest display or POST path instead of starting over.
Open no-POST guide Open no-display watch page