Member Avatar for AlbinoBlackShee

Hi

I built a basic PC for a family friend, really basic. He just fetched it me to say, he'd switched it on as normal but the system didn't switch on.........

I Have looked at it, changed the case and the PSU, but I still can't get it to switch on, even tried a new Mobo to see if thats the issue, still nothing:mad:

Please help, he needs it for tomorrow.

Thanks

ABS

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  • Latest Post Latest Post by Chaky

Dani AI

Generated

Given the swaps already done by and the front-panel checks and questions from , the absolute “no life” symptom (no LEDs, fans, beeps) points away from a loose switch and toward power-rail, chassis-short, or motherboard/CPU-power-stage failure. The checklist below is ordered to get a quick, safe triage without repeating earlier steps.

  • Safety first: mains unplugged when moving parts, wrist strap or frequent grounding, and a basic multimeter or a cheap PSU-tester on hand.
  • Verify standby and main rails before deeper disassembly: with the PSU plugged in and switched on, measure purple-to-black on the 20/24‑pin for +5VSB (about 5V). Also spot-check yellow/black (+12V), red/black (+5V) and orange/black (+3.3V). Absence of 5VSB usually gives zero lights/response.
  • Confirm the CPU auxiliary feed is present and fully latched (the 4/8‑pin ATX12V connector). Many boards refuse to show any life if that feed is missing or the cable is damaged.

If the rails look correct, isolate the board from the case: place the motherboard on an insulating surface, connect only PSU + main 24‑pin + CPU auxiliary + speaker (if available), and attempt power. If the board lives on the bench, the original failure was likely a short from a standoff, screw, or misplaced header. If still dead, inspect for physical damage (burnt components, swollen capacitors, bent socket pins) and confirm CPU/motherboard compatibility and that the VRM area isn't visibly damaged.

If these checks are uncomfortable or inconclusive, a known-good PSU or a shop with a bench supply/POST card will quickly identify whether the PSU, the board’s power circuitry, or the CPU is the culprit. Handling live measurements without the right tools can be dangerous; if unsure, professional bench-testing is the safest next step.

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Member Avatar for Chaky

Maybe the switch is not connected properly or faulty.
Try shorting the 2 pins on the motherboard that the switch is connected to.
Some PSU-s have switch on them (back side). Maybe you missed it.

Member Avatar for Chaky

Are there ANY lifesigns? Lights, beeps, fans spinning?

Member Avatar for Chaky

You said that you tried different PSU and different Motherboard.

It's down to CPU. Some motherboards make beeps even without CPU installed. Try uninstalling CPU an see what happends. Make sure you're grounded and use those gloves.

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