PC Turning off while booting (even before POST)

[mark0909]

Dear community,
I have a problem with my machine.

Sometimes (apparently on a random basis) it turns off with no error screen report, no bluescreens and no messages in the Windows Event Viewer. It sometimes does that even before the POST phase, as soon as I press the power button.

When the systems reaches the Windows Login screen, the machine seems to be stable on.

This is what I tried:
- Analyze events in the Windows Event Viewer
- Memetest the RAM
- boot into Ubuntu (even if I think that it's not OS dependant)
- unplugged all of the external devices
- completely unplugged everything, even the mobo.

I also breadborded the system, but the issue seems to be hardly reproducible, or at least I am missing something.

When it turns off, the vents stop rotating. To recover I have to physically unplug the power cord, wait for a couple of minutes and the try to turn it back on.

PS: I had a look at the troubleshooting guides here on TH, but unfortunately they did not help.

Any idea?

Thanks.

 

[getochkn]

Sounds like a bad cap on the motherboard that needs time to drain and recharge and its having a hard time doing that and thus messing with the power on and off and unplugging to remove standby voltages, etc, seems to fix it. Best solution for now, don't turn it off. lol.

 

[wysir]

Another issue to consider would be the cpu is overheating and the temp is causing the BIOS protection fail safe to automatically shut down the computer.

 

[mtxpeterson]

Have you used a psu checker? I've had psus that were beginning to fail do that.

 

[mark0909]

Another issue to consider would be the cpu is overheating and the temp is causing the BIOS protection fail safe to automatically shut down the computer.

The CPU, GPU and mobo temps are fine (40 degrees C). Thanks.

Unfortunately I don't have a PSU checker to use

 

[mtxpeterson]

Another issue to consider would be the cpu is overheating and the temp is causing the BIOS protection fail safe to automatically shut down the computer.

The CPU, GPU and mobo temps are fine (40 degrees C). Thanks.

Unfortunately I don't have a PSU checker to use

You can find a few that relatively inexpensive. There is also a bit of a trickier tactic you can do, is that can jump the psu, and use a meter to check the voltages. There is info on the web, but I wouldn't advise it if you aren't experienced with it.

 

[mark0909]

I came back home minutes ago and I can confirm that the computer does this only on the first start.

It's kind of strange...

 

[mark0909]

It seems strange to me that the PSU is failing (it's a high end Enermax). I would check the MOBO first. Any other advices? Thanks

 

[mark0909]

After some more in depth testing, I can confirm that the faulty component may be the MOBO or the PSU. I ruled out other hw parts (gpu, hdd, ssd, fans, case, ram).

Thanks.

 

[mtxpeterson]

After some more in depth testing, I can confirm that the faulty component may be the MOBO or the PSU. I ruled out other hw parts (gpu, hdd, ssd, fans, case, ram).

Thanks.

Glad to help we can help. I wish I could offer a more definitive answer to your issue. Always learning that hardware is most certainly unpredictable. I hope you will share what it finally is. I am curious now. Best of luck.

 

[mark0909]

I found a spare 600w OCZ PSU, known to be working. With this I hope to test the mobo. I'll let you know.