The PC shut down unexpectedly and is no longer starting.
The PC shut down unexpectedly and is no longer starting.
My daughter was using her phone instead of the PC, but it just shut off. I was nearby and could confirm she didn’t do anything strange to it. There wasn’t a blue screen, just a loss of power, and now it won’t boot at all. When I press the power button, only the fans spin slightly (case and CPU fans), and nothing else happens. I’ve already changed power strips, switched to another outlet, and tried a different cable. All USBs and the network cable were unplugged, and I checked the switch on the back. I’m still unsure what might be wrong. This PC was built for Christmas, and all components were new, so it’s possible but not certain. It was running Windows 10, which I prefer over 11.
I’m uncertain about the next steps. Without extra parts to test, I probably need to buy replacements if something fails, though I’m not sure what else might be at fault—besides the power supply. Could anyone help identify possible causes or suggest additional details?
I’ll look up the specific parts list if needed. Here’s the power supply info:
https://www.amazon.com/gp/product/B01MTJ...UTF8&psc=1
An EVGA Bronze 600BQ (600w)
Power down and unplug, then open the case.
Remove dust and debris.
Check visually and by touch to ensure all connectors, cards, RAM, jumpers, and case connections are securely in position.
Possibly some parts may have shifted slightly due to expansion, movement, or vibrations.
Examine with a bright flashlight for any signs of damage.
Look for metal-to-metal contacts that might be causing a short circuit.
Inspect standoffs, I/O panel, and check for worn or melted insulation on wires.
Thank you for the update! All components were cleaned thoroughly and repositioned, along with wires and cables. I searched for signs of damage but found none. Also checked the PSU by smell just in case. Disconnected everything except the RAM and CPU, including USB headers, but the MB power port remained connected. The case and fans briefly powered on before shutting off completely, with no further activity observed.
It seems the CPU might be overheating during startup and could be shutting down due to thermal issues. You might need to replace the thermal paste. This would require taking out any coolers or fans, cleaning the old paste, and applying fresh one. Since you assembled the PC yourself, you likely understand that thermal paste is a common problem area. It’s unclear what else to do, but there could be other solutions—feel free to explore further ideas.
I could clean and reapply the paste before, having done so on another machine, but I’m not sure. The small amount of power that reaches it barely causes the fans to spin even once, so it seems unlikely there’s enough time for it to start or heat up properly. I value your advice though. I ended up getting a new PSU from Amazon; although I don’t like the process, I’ll replace it but return the original if it’s the real issue.
Consider investing in a quality power supply for proper diagnosis. I believe you purchased a superior model.
Since the fans only spin slightly at a moment, it seems a bad power supply unit might be the issue. A hot CPU from insufficient thermal paste or a defective CPU cooler could cause the fans to run longer.
It could be a bad power supply unit. If it stops working between a 1/10 second and a 1/2 second, that’s a strong sign. The PSU will perform a self-test of its voltages when it powers on; once stability is reached, it sets one of the ATX power pins to +5VDC. If this doesn’t happen, the CPU won’t start. (EVGA might also have protection mechanisms to cut power in case of issues.) You can remove all power connections and try the paper clip test to see if the PSU starts at all. A more reliable method is to take the PSU to a shop with an ATX PSU tester, or purchase a cheaper one. EVGA offers warranties for their units (90 days to 10 years). If you bought the PC in December, consider returning the PSU via RMA.