PC powering off problem

[Booldawg]

My PC has taken to suddenly switching itself off at random. When it does this, the only way to start it up again is to remove the power cable, and plug it back in otherwise the power button simply wont power it up. I'm not sure if its a PSU problem or has a short somewhere. I've tried rattlling the case about when the pc is on and this doesnt seem to invoke the mysterious power-downs. Any ideas?

[peanut]

Check to see if your cpu fan is running. if it is not, the computer is turning off to protect itself from an overheating cpu. cpu is the processor, it will be the only fan on your motherboard.

[Booldawg]

yes the cpu fan is running, i've been running it with the sides of the case off, to check for cables fouling the m/board etc.

[tellboy]

Also check the small fan on the Graphics Card same sympton.

[Booldawg]

thanks for the advice, i'll have a look

[dodgyshirt]

Overheating problems can cause the PC to shut down but would not likely be the reason for it's re-starting difficuties.

I think your own suggestion is a more likely cause.

Check the System Panel connector plugs on the motherboard to ensure none of them are loose, check the wiring to these from the case power buttons and if possible replace the mains power lead.If none of these work, as a last resort replace the PSU.

The most likely cause is a dry joint in the wiring or a looseplug.

Last of all, don't rattle the case, this could cause even more problems.

[peanut]

ok, your fan is running. now check to see if the cooling fins behind the cpu are clear of dust. Im not saying it is your cpu but if the cpu is too hot and makes the computer shut down, it will probably not immediately restart until the cpu cools. Then again there is a possibility there is a worm, virus or trojan horse in there causing this behavior.