Shuts down on power up
 

On powering up my desktop, it starts to go (fans start), but after only one or two seconds there is a bleep and it powers down, leaving the power LED flashing.

I only seem to be able to cure this by removing the power cord for a while but that doesn't always work.

Is this a mobo problem or something else?

thanks


B

sounds just like what mine did when the mother board went to the big sky lol

Could be something else besides bad MB. Ram could be bad or installed wrong. I had a similiar problem and it was the onboard video. Installed an old card I had lying around and it worked fine.
Any major component in the power flow could do it.
OR you could have a bad MB!!
It's like any electrical problem. You have to go item by item and check them all.

Thanks. I was hoping that would not be necessary.:eeek: But, here we go!

Is it saying anything about your PBR,primary boot record? I'm having that problem no on a dell desktop.
A pain in the hoohaw.

general power off and restarts on powering up are 99% of the time hardware related, and usually something is either dying or shorting your system. I've seen everything from RAM, floppy drive, frontside firewire connectors, and processors do this, so the range is basically everything in your case... sadly. If you figure out which piece it was, let us know :)

I really think it is a hardware problem, too, William. But I do not have the tools to check every individual component. :(

It first occurred when I was changing around some hard drives. In order to ghost a drive I added an extra drive without screwing it into place and left it dangling. At first I thought it had shorted, but now I don't think it did because something would have failed immediately, not on reboot. The IDE cable looked a bit iffy so I changed it for a new one.

Having finished my work on the drives I installed the two that were going to remain in that computer in their proper place.

I was advised to check the tops of capacitors on the MB for bubbling, as this is a common cause of impending failure, but all was OK.

The case has been put back on and the machine has been running for a few days and seems fine. But I am concerned about turning it off as it might not switch on again!


Brian

It's an odd problem as I would have half expected some kind of intermittant fault whilst the machine was running if it was indeed a short somewhere along the line.

Having said that, it should still be possible for you to test some of the hardware in your case - You're not guaranteed to find the culprit but it at least means you won't need to buy any extra hardware and/or equipment.

If you've got more than one stick or RAM, try taking one out and seeing if that works, If not, swap it and try the other one in bank one. Also, disconnect any hard drives or DVD/CD-ROM drives one by one before rebooting and see if that cures anything. If you have any non-critical expansion cards like sound or network, remove those one by one as well.

Like I said, you may not find the problem if it is graphics, CPU or motherboard related, though you can at least rule out the above hardware.

That looks sensible. Thanks :)

Thanks for everyone's help.

I swapped out the PSU and the problem went away!

(that's good because a new motherboard would have meant a new chip and fan, a new graphics card, new memory AND and a new hard drive: all the existing ones are serviceable but would be incompatible!!!)

:)