Pinpointing Electrical Problem/PC Switching Off

[Tatterdemalion]

I am having some problems with a PC that is switching itself off and am hoping that if I describe some of its symptoms people may

be able to guide me to which component(s) could be faulty and if and how I can revive my machine.

The PC is a Desktop unit running Windows XP Pro SP2. It has two internal hard drives, an internal floppy, internal CD-Re-Writer

and internal DVD-Rom (the last of which no longer recognises ANY type of disc). I also keep a couple of external USB hard drives

connected.

Recently I have been able to get the computer to boot to the XP Desktop screen. All my program icons have been properly

displayed and the Splash screens for my soundcard and Iomega Peerless have popped up as expected. However, after that point the

orange "busy" light would indicate activity, blinking very rapidly, and I could hear a series of "clicks" from within.

I don't know what the computer would be looking for at this stage.

The clicking would cease and the image signal to my monitor be lost whilst the computer's orange "busy" and green "power" lights

stayed on. The system fans could also be heard.

After a period of about 20 minutes a squeak would sound as the DVD-Rom and CD-RW were recognised and Windows would

appear to re-boot from scratch (it never reports any power failure) but with a successful outcome following this second attempt

where the PC would stay on for any amount of time with no "blacking out".

Today "second time lucky" has not worked for me. I can still boot to the Desktop and everything seems perfect until the orange

light shows some thwarted activity - as it does so I can hear "little engines winding down" then I lose the signal to the monitor and

the orange and green lights remain on but now only for a short time before all power is lost.

Following this the PC's power-on button does not respond until I unplug and replug at the mains. After which the cycle repeats.

Any insights would be hugely helpful......

[Fed]

Try unplugging the usb HDDs.
Try starting in safe mode.
Try turning off Auto Re-boot on System Failure.
Do one thing at a time. testing in between.

[Tatterdemalion]

I tried to start Windows in Safe Mode - by pressing F8 - but I must have got the timing wrong because the full OS loaded and I lost power again in the established pattern.

The image to the monitor vanished and the orange and green power lights remained lit for a short time until they extinguished rendering the Power On button inoperable prior to unplugging and replugging at the mains.

What's different now is that when I re-power it, it isn't showing me any signs of attempting to boot. It's as though it's still locked in the same looping stage. The orange and green lights glow and then go out as the whole machine loses power that can't be re-accessed without unplugging and replugging at the mains.

I should probably point out that the first trouble I had with this machine occurred last April. I have two internal hard drives. I use C for most programs and the OS and D for data and ALL of my e.mailing activity (both the software and the messages). One day last year, I was using my e.mail program when the computer completely blacked out.

On re-booting, Windows reported the error and said that it had to repair some files on Drive D. It did so but following this I had a few weeks where I would get the "second time lucky" booting/power loss scenario. It didn't happen every single time and after I bought a new Surge Protector plug socket the problem went away completely for several months until it started again about three weeks ago.

Is there anything I can do to physically "re-set" the computer so that it can try to start Windows again ?

[Fed]

Try safe mode again, if it won't start in safe mode you better start looking for your OS disk.

[Tatterdemalion]

I thought it wouldn't start because the electricity was turning off.

[Fed]

I thought it wouldn't start in safe mode because you got the timing wrong and it booted into normal mode.

[Tatterdemalion]

Yep. I did that and then it switched off (as before) except that now when I try to re-boot it's switching off before anything happens - like it's stuck in a loop in a sequence.... it wants to continue from where it hung rather than go right back to a fresh beginning.

Until today I wasn't getting the issue where after losing power you couldn't press the power button to start it up again UNTIL you had unplugged at the mains.

Perhaps if I unplug it at the mains and leave it for a while - I'll be able to come back and switch it on so that it will at least be able to try to get a run up at Windows before it sighs and dies.

[Fed]

I'd try unplugging D drive as a test too.

[chudney]

[size=20][/size]

if your computer is turning itself off within a 15 to 30 minutes the problem is the motherboard try find some electronics experts because i cannot help you with that

i have also a problem like you i have a computer that cut out a power when an error message occur.....

i did ask an advise and told me to replace my motherboard.......

there are IC's where burn slightly ok!!! cause of statics