Question PC turned off randomly and now won't boot

[Leaven]

My daughter was sitting at her PC but on her phone not watching the screen when it just turned off. I was in the room so I know she didn't do anything unusual to it. Didn't have a blue screen just seemed to lose power, now it won't boot. When the power button is pressed the fans spin just a tiny fraction (case and CPU fans) then nothing else happens. I've already tried changing power strips and to a whole different outlet, as well as trying a different cable. I disconnected all the USBs and network cable as well, and checked the switch on the back. After that I'm a bit at a loss. I built this PC for Xmas and all the parts were new, so it seems unlikely one has already died but possible. It was running Windows 10 because I don't care for 11.

Not really sure what next steps to take, I don't have extra parts lying around to try swapping them all out, so I'd likely have to buy new ones if something died, but I'm not sure what (other than the power supply of course). Can anyone tell me what might cause this or what other info I should provide?

I'll have to look up the specific parts list but can add it if needed. I know the power supply is this:
https://www.amazon.com/gp/product/B01MTJTO2O/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
An EVGA Bronze 600BQ (600w)

 

[Ralston18]

Power down (off) , unplug, open the case.

Clean out dust and debris.

Verify by sight and feel that all connectors, cards, RAM, jumpers, and case connections are fully and firmly in place.

Something may have wiggled a bit loose due to expansion/contraction and vibrations.

Use a bright flashlight to inspect for signs of damage. Some sort of metal to metal contact that could be causing a short. Standoffs, I/O panel. Maybe a wire with rubbed off or melted insulation.

 

[Leaven]

Power down (off) , unplug, open the case.

Clean out dust and debris.

Verify by sight and feel that all connectors, cards, RAM, jumpers, and case connections are fully and firmly in place.

Something may have wiggled a bit loose due to expansion/contraction and vibrations.

Use a bright flashlight to inspect for signs of damage. Some sort of metal to metal contact that could be causing a short. Standoffs, I/O panel. Maybe a wire with rubbed off or melted insulation.

Thanks for the reply! All cleaned and I removed and re-seated RAM and GPU, plus wires/cables. Looked for some kind of evidence of damage but didn't see any, tried to smell PSU as well just in case there was something I missed last night. Tried disconnecting everything but RAM and CPU, including USB headers and all that, only left MB power plugged in. Case and CPU fans still power for a split second and then stop, no other activity.

 

[Ralston18]

Maybe the CPU is overheating at startup and thermally shutting down.

May need new thermal paste.

That would involve removing any coolers/CPU fans, cleaning off the old thermal paste, and re-applying new thermal paste.

Because you built the PC (kudo's) you probably have a better sense of it all regarding the thermal paste as being an issue.

Is it viable for you to clean and reapply new thermal paste?

Not sure what else to suggest. However, there may be other ideas and suggestions - I have no problem with that.

 

[Leaven]

I could clean and reapply the paste, I've done that before on a different machine, but honestly I doubt it. The tiny bit of power that does get through barely makes the fans rotate even once, so I don't think there's time for it to even begin startup, let alone actually heat up or detect that it was too hot. I appreciate the suggestion though. I ended up ordering another PSU from Amazon; as much as I don't like doing it, I'll swap it out but return the new one if that's not the actual problem.

 

[Dark Lord of Tech]

Might want to invest in a decent PSU , to properly diagnose. I hope you ordered a better model power supply.

 

[lojikal]

My daughter was sitting at her PC but on her phone not watching the screen when it just turned off. I was in the room so I know she didn't do anything unusual to it. Didn't have a blue screen just seemed to lose power, now it won't boot. When the power button is pressed the fans spin just a tiny fraction (case and CPU fans) then nothing else happens. I've already tried changing power strips and to a whole different outlet, as well as trying a different cable. I disconnected all the USBs and network cable as well, and checked the switch on the back. After that I'm a bit at a loss. I built this PC for Xmas and all the parts were new, so it seems unlikely one has already died but possible. It was running Windows 10 because I don't care for 11.

Not really sure what next steps to take, I don't have extra parts lying around to try swapping them all out, so I'd likely have to buy new ones if something died, but I'm not sure what (other than the power supply of course). Can anyone tell me what might cause this or what other info I should provide?

I'll have to look up the specific parts list but can add it if needed. I know the power supply is this:
https://www.amazon.com/gp/product/B01MTJTO2O/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
An EVGA Bronze 600BQ (600w)

Given the fact that the fans spin just a fraction of a second IMHO it sounds like a faulty PSU is likely the culprit. An overheating CPU due to lack of adequate thermal paste, faulty CPU cooler would actually allow the fans to spin for a longer time.

 

[AntonyLovric]

Might be a faulty PSU. If it's shutting off between a 1/10 of a second and a 1/2 second it's a good indication.

The PSU will do a 'self-check' of it's own voltages when powering up, when things have stabilized, it sets on of the ATX power pins to +5VDC. If things are 'not good', that voltage won't be set and the CPU won't start. (EVGA also might have their own protection at play to shutdown the power in event of an error.

You can unplug ALL the power connections in the computer and try the paper clip test, to see if the PSU powers up at all. A better test would be to bring the PSU to a shop that has an ATX PSU tester. (or you can buy a cheap one)

EVGA has warranties for their PSUs (from 90 days to 10 years). If the PC was bought in December, try to RMA the PSU.

Power good signal - Wikipedia

en.wikipedia.org