PC will turn off by itself after a few seconds, seems like a MoBo problem.

G3Kappa

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Nov 9, 2014
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Greetings.
About a week ago I had an unfortunate accident with a sugary, non acidic, beverage. That is, I've spilled some on my motherboard.
My course of action was the following: immediately cut off the power, use a rag to absorb most of the liquid, dry it off with a hair dryer and let it air dry for about two hours.

And then it didn't want to start up. Well, of course I'd add. I had just spilled liquid over it. What's odd, though, is that I tried to turn it on a while after, and it worked. It worked fine, perfectly for the two consecutive days that it was on. Then it went into sleep mode, and when I tried to wake it up we were back to the beginning. After a few hours, again, it worked. This went on for about 3 or 4 days. Now however it just gave up and won't start, no matter what I do.

I'll try to detail the problem as best as I can:
After pressing the power button, every fan starts rotating, the GPU lights up normally, a second passes and then the PC shuts itself down. So it tries again, in a loop that goes on until I turn off the PSU.
Before explaining what I tried and what I did not try, I want to add another bit:
If the power is off, and I hold the power button for a while, the aforementioned sequence lasts for up to 3 seconds. Then, back to one second.

And this is what I've tried so far:

1. Remove every non-essential component
2. Replace PSU
3. Reset the CMOS
4. Reseat every single cable
5. Clean the MoBo of any sugary leftover with a moist sponge, and let it dry

I still didn't try to reseat the CPU, but it seems firm and I don't have any thermal paste at the moment.

I've googled everything that I could think of, and at the moment my best lead is that a capacitor on the motherboard died. They all look fine to me, though.

And here we are. I don't know what else to try, especially since I'm not a hardware expert. It doesn't look like major damage, since when it starts then it runs fine, but now that it stopped successfully booting I'm growing more worried.
Thank you in advance for any reply.

 
Solution
Your problem only started after the mishap with your drink. So unless the power button got hit with the stuff, I don't see how it can be the cause.

G3Kappa

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Nov 9, 2014
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Can I just pick any fan header? My MoBo has them labeled (CPU_FAN, SYS_FAN, PWR_FAN ...)
Also I don't think it's the PSU, since I've tried another one and got the same exact result.
 

G3Kappa

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Nov 9, 2014
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Alright, I've tried what you said but unfortunately the result is still the same.
 

G3Kappa

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Nov 9, 2014
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Seems like I'll have to. On a related note, I've found something that might or might not help, in another thread:


That thread didn't get any more replies, though.
What do you think, should I give it a shot?