Motherboard not being powered.

shizanky

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Nov 27, 2011
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I just assembled my new computer and have run into a problem. Before I had put everything in the case I tested the motherboard with the cpu/fan/gpu etc. and it booted up fine including the post beep.

I then assembled it inside my case, making sure the standoffs were correctly placed, and the cords were plugged into the right places etc. It looked like everything was good to go. I hit the power button and it turned on for about a second and instantly shutoff. I went back and made sure everything was correctly wired and it seemed ok.

After a couple attempts trying to get it to come on and getting the same instant power off, and sometimes no power at all, I took the mother board back out of the case and tried the external boot again. I did everything exactly the same as my first test boot, but this time it's getting no power at all.

I tested my power supply and it wasn't the problem. I had been discharging myself on one of my metal side panels that I had removed to keep the static away from me.

I can't seem to find the problem... please help!
 

shizanky

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Nov 27, 2011
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Alright, so I took the gpu out and put it in another computer.. and the same thing happened. When I go to power it on, it shuts off instantly. Now going back to when I had assembled my new computer, I had done that twice (Powering it on and it shutting off right away) and after that it did nothing. I'm scared to try it again in the old computer as I don't want that to malfunction either. Is it possible my gpu is faulty and fried my new motherboard from attempting it twice?
 
Was there any trauma to the motherboard or video card between the time it worked and when it didn't?

Did you touch internal parts when the power was on in the first test?

If the video card has touched multiple computers and only the video card, and every computer acts the same (bad) way afterwards, it does sound like it is a bad video card.

I don't see why it should have worked the first time and not the second time, though, unless there was trauma to the video card some time between when it was working and when it wasn't.
 

shizanky

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Rolli, I've tried the whole breadboarding thing. I'm getting absolutely nothing on my mobo now. It is a possibility it's the cpu, but it had worked fine before I had put it inside the case and hooked everything else up.

Raiddinn, There has been no trauma to the gpu, other than the possibility of static, which I had been discharging myself the entire time every time I went to touch something.

The only thing I can think of that went wrong and I'm just assuming this is possible... The gpu is faulty, and when I had it in my new build and tried powering it on the second time, it fried my motherboard. What leads me to believe this is the fact I put it in my old computer that runs perfectly fine with my gtx 260 in it with a 750w psu, it did the EXACT same thing it did to my new build - shutdown about half a second to a second after I turned my computer on.
 

shizanky

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On my first test boot, outside the case, the gpu worked fine. Fans came on, mobo powered up. Everything was great. Once it was inside the case with everything else hooked up, it shut down instantly. That made me think a bad psu. But just for kicks I tried the new gpu in the old computer, same thing happened on a for sure good psu. Sorry for repeating myself here but could it actually be that my gpu fried the motherboard on that second attempt to power it on in the new build?
 
I find it unlikely.

My gut feeling is that you are shorting tings out with something you did inside the case.

I haven't seen very many scenarios at all where a video card worked right exactly one time and there was no damage to the card after that one time. It is infinitely more likely to work 0 times or some number much higher than 1.

If a video card does work 1 time and never again, in my experience it is usually a driver problem. Like the wrong driver was installed and then the computer can't resolve this problem till windows gets reinstalled. That, however, doesn't sound very applicable here.

The second most likely reason that I can think of for it to work one time and no more would be if the video card somehow overloaded the PSU during the breadboarding.

Can you tell me more about your PSU? Maker, Model, how old is it, usage patterns, etc.

Also, what are the same statistics for the video card?