PC shuts down after 0.5 seconds

Okay, yet another problem has occured. I shut down the PC yesterday, the correct way. When I tried to start it today, the lights in it will lit for half a second, same with the sound from the fans etc. Then it just shuts down, and if I want the same half a second of light and sound, I must plug in and out the power cable. After the first try, nothing happens when I press the power button. Any ideas? It hasn't been touched since I shut it down yesterday. Also, there is light in the motherboard, so it isn't problems with the power.

My first tought is that some component is broken. Is there any way I can check this, except for trying every single piece into another computer?

 

My current suspect is the power supply, a MIST 500W. I have no idea how it might have get broken, but I'll test with another power supply when I receive my old one.

 

Cellon,

I have this same problem and I replaced the power supply. There was no luck. How did you resolve this?

Thanks,

 

In my experience this is generally a fried/dead component creating a hard short. This trips the power supply out.

Try removing everything but ram and processor.
See if it will POST.
If it does, add one piece of hardware back in at a time until you find the faulty component.

 

Try disconnecting molex power connectors to dvd/cd roms and hard drives just leave the motherboard power connector in then see if it shuts off? Let us know what happens

 

Sorry xmeister I really should refresh the page before posting :-o

 

Hi Cellon,

The guys are correct. Power supplys usually have over current protection and will shut down when it happens. The only way to reset the protection circuit is to remove all AC power as you have been doing. A dead short will prevent the supply ever coming on. Half second indicates heavy current. The advice to remove all loads and put them back one at the time will narrow the problem down rapidly.

Good Luck, Jim

 

The problem in my case was a fried motherboard due to a loose screw.

 

Hi Cellon,

Good Job! Thanks for the feedback>

Jim