Computer keeps turning off

[dude112]

Hi all,

My computer keeps turning off after about 20 seconds when i turn it on. It doesn't reboot but turns itself off without warning. I see the windows loading screen and then it turns off. Booting in safemode doesn't help either. It also turns off when in the Bios.
I managed to get into the hardware monitor within the Bios before it turned off and the temperatures seem fine.
When continuously turning the computer on it turns off even quicker and after a few tries it turns off immidiatly. The power stays on though and i can turn it on immediatly... only to have it turn off again though.

Before this happened the computer did turn itself off a few times but only after it was on for a while. But now I can't even get to the desktop.

I didn't do anyhing before this thing happened. No installing stuff or whatever.

I've tried a different PSU, switched RAM and reseated the heatsink without any succes.

Because it also turn off when in the bios I'm guessing it isn't the HDD that's causing the problem.

My system specs are:

Asus P4S800 mobo
P4 3.2Ghz
2x 512MB RAM
7600GS 256mb videocard
antec 380 earthwatts
HDD, dvd-rom, dvd-rw, floppy
Windows XP pro if that is of any importance

if anyone could locate the problem that would be great.

Cheers

 

[KurrentEweser]

Try letting it run while in the bios with all drives disconnected and see what happens.

 

[SirCyber]

sounds like something is going out, i.e. cpu or a chipset. do you have a power supply tester? switching psu's may not solve the issue if you are not testing them, they could both be bad on the same rails. I'm definately leaning towards motherboard or cpu. sorry on that dude

 

[dude112]

I've tried running in bios while disconnecting all drives and it seems to have solved the problem.

At first I forgot the floppy drive and the problem remained. When I disconnected the floppy it didn't turn off.

Turned on the computer with the floppy drive disconnected and it worked. But then I connected the floppy to see if it really was the problem and the computer booted fine this time.

So i quess for some reason the porblem was solved by disconnecting all the drives.

thanks for the help. I hope i won't be back in this topic again

Edit: I was mistaken. The problem has not been fixed. The computer turned off by itself again. It also tuned off when all drives were disconnected.

@ SirCyber: I don't have a psu tester... As for the mobo and cpu, i hope you're not right but it seems that something IS broken. Just need to find out what.

 

[Ventriac]

If it was the hdd it wouldn't shut off it'd go to a black screen I believe... I'd agree with someone above saying that's something's going... Check your heatsink fan make sure it's going full boar, stock heatsinks suck and like to die. So make sure that it's going full speed, also keep it off for a long while and try to turn is back on and see if you can check your temps, but if it doesn't turn on after you letting it sit, it's prob the mb or cpu.

Do you hear beeping when you start it up?

 

[dude112]

There's no beeping or any other suspicious sounds when starting up.
The CPU temperature was around 60C in the hardware monitor in the bios before it turned off.
All fans are working properly.

And apparantly if it does boot to desktop it'll turn off at random times. That does look like it's an overheating problem although the temps on speedfan looked fine before it suddenly turned off.

Is it common for defective mobo's to just turn off? The light of the mobo stays on though.
Same question goes for the processor.