Member Avatar for iso111

Im trying to figure this out. Pls help give more direction.
I have a voltage detector and a micro detector.
Once abou 6 mo ago, I was out during a rain storm to return and have difficulty turning it on.
Since then PC would work fine, but once in a while wont turn on. The latest time a week ago, I dismantled the on/off button in an effort to close circuit the two wires, in case the problem is in the on/off button. no luck.( Sometimes tapping the side of the PC turns it on after I push on/off.)
But that time it turned on by turning the power button in the back off then on.
I detect electricity current in the power cable, and possibly some potential in the main on/off button on the front of the machine. I move the speaker wire plug in and out and get some static sound.
Currently the PC doesnt respond to any thig I try. Tried Plugging in and unplugging as well.
How can I determan if the problem is in the power supply box, the on/off swicth or somethingg else?

1 to 2 year old white box windows 7 PC. water cooled video card and processor.
Thanks,
Ross

  • 2 Contributors
  • 1 Reply
  • 341 Views
  • 2 Days Discussion Span
  • Latest Post Latest Post by rubberman

Dani AI

Generated

Based on 's description (intermittent no‑power after a storm, case tap sometimes starts it) and 's follow-up, the pattern points away from a simple front‑panel switch fault and toward either the power supply, a motherboard short/corrosion, or a loose connector. The fact that toggling the rear PSU switch sometimes starts the system is a useful clue: treat the PSU and any water/corrosion damage as prime suspects.

Recommended diagnostic steps (in this order):

  1. Safety first: unplug mains, wait 30 seconds, and discharge capacitors by holding the front power button for 10–15 seconds with the PSU disconnected. Work on a non‑conductive surface and avoid touching components with bare hands.
  2. External quick checks: try a different wall outlet and power cable (or plug directly into the wall, not a strip). Confirm the PSU rear switch and inlet are clean and solid.
  3. Visual inspection: look for corrosion, green/white residue, bulging caps, burn marks, or damp or dried water traces—especially around the ATX 24‑pin, CPU 8‑pin and GPU connectors and around the VRM area.
  4. Isolate the case front panel: unplug the front‑panel power switch header and momentarily short the motherboard power pins with a small screwdriver to rule the switch/wiring out.
  5. Minimal boot: with power off, remove all nonessential devices (drives, extra RAM sticks, add‑on cards). Try to power with only CPU, one RAM stick, and PSU connected. This isolates a bad add‑on.
  6. PSU test: if available, use a PSU tester or swap in a known‑good PSU. A paperclip test only proves the fan runs; a proper test or swap under load is definitive.

If the system still won’t respond but a known‑good PSU works, replace the original PSU. If a known‑good PSU also fails, the motherboard likely has a short or failed power circuitry—cleaning with high‑purity isopropyl and careful drying can help for corrosion, but component‑level failure may require repair or replacement. For safety and accuracy, consider professional service if mains work or board repairs are outside experience.

Member Avatar for rubberman

So, the PC is not a laptop/portable unit? It started acting like this after a big rain storm? Is this correct?

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.