PC Shuts Down within 30 secs of booting

P4 Duo Core 3.4Mhz
Gigabyte 775 mobo
XP

I had a PSU fail and have replaced it with another unit. The PC boots ok (always gets to POST) then shuts itself down at variable points along the way to fully booting into XP.

Suspecting that the original PSU failure may have fried some components I have sytematically removed every card and unplugged every device until all I have connected to the PSU is the mobo and the HDD I'm booting from. Still no joy.

Does this mean that some component on the mobo might be fried and the system is shutting down because it is having a fatal hadware fault? :mad

How could I check for this?

 

Is there no one who can help / offer a comment?:confused

 

This is a very real possibility. But the problem could be a corrupt Windows XP, or a thermal problem. Go into your BIOS and find the Hardware Monitor (sometimes called PC Health also) and see what your system temps are. Leave the PC running for awhile and watch the temps. You could also boot to a CD-based OS like a BartPE CD or the UBCD4Win or a Knoppix CD. If the PC stays running when using one of these "live" CD's, then we know the problem is either your hard drive or your Windows install....

 

Does it do this in safe mode?

 

Thanks for the sugggestions.

Firtsly, the PC never gets far enough in the bootup process to allow me to select Safe Mode, nor even interrogate the BIOS for system temps.

I have noticed that the first time I try to start it is the longest time it will stay "alive". Then if I do an immediate restart it doesn't get quite so far, then a third time it gets less far again. Why would the interval that it can run be getting less on each subsequent restart?

I have the covers off the machine, it is dust free and the ambient temp is about 20'C so I'm struggling to think that it could be a heat issue.

Anything else I can try?

 

Check the heatsink on the cpu, taking bets its loose, or the thermal compound is burnt up. ed

 

Motherboard should have a jumper that you move to short the heat sensor which diables the heat sensor.

What happens when you power on without a CD in the drive?

You could also try booting with keyboard and mouse unplugged as these could be causing hangup.

Is this a VISTA computer that you are running XP?

Is there a sensor that tells when the cabinet is open?

Try removing harddrive and CD drive, then power up and see what happens.

Try booting DOS from a floppy drive with a DOS formatted system disk.

Check again that all cable connectors are fully seated.

Spray the motherboard with can of cooler to see if that keeps you going longer.

Just some thoughts.

 

OK we have a system that starts the processor and then shuts down.

I take your point that you don't get far enough to use the bios let alone any operating system.

Folks?

When it starts do all than fans spin or is there one on the graphics card that sticks?

First check Ed's elegant heatsink suggestion if this doesn't sort it then.

I have seen this behaviour with a failed card shorting a bus. Take them all out, including the graphics.
You will obviously get no picture, but does the motherboard stay running?
I have also seen it with problem devices connected, especially via USB - Remove them.

Take your memory modules out clean them and reseat.
Put them back in one at a time, with a reboot between, unless you have dual channel.

let us know how you get on.

 

I'm thinking this may very well be a thermal issue (as I mentioned in my first reply a few days ago). It could also be a bad motherboard or PCI/video card or even a bad memory chip. You say that you can't even get into BIOS- that the PC doesn't stay on long enough? The BIOS is like the very first thing that comes up; so that would mean that the PC is shutting down or spontaneously rebooting after less than 6 or 7 seconds.... if it gets past the POST screen, you should try booting to a live CD just to see if it's possible. I would also follow studiot's advice and remove all cards (be sure the power cord is unplugged from the PC) and re-install them one at a time and see where that gets you.....
Happy Thanksgiving Everyone! :yum

 

OK, it's working now!

Seems the issue was as "tunered" said - a thermal one. I checked the CPU heat sink and sure enough it was loose! (Don't know how that happened?)

I ran Everest to check the system temps and the CPU runs in the range of about 65'C to 77'C. Is that normal for my type of processor? (P4 Dual core 3.4GHz).

 

that is too hot for cpu . did you apply new thermal paste? when resetting cpu fan new paste is a must or else temps rise as yours are

 

Yeah I would like to see 35C but 55 - 65 would be normal.

Remember all ratings are given at 25C and deteriorate with increase above that.

 

65c would be max under load (100 %) I have a pd 930 @ 3 gig that I just sold to a friend that idles at 39c max temps 56c under stress testing.

 

Ok, I reapplied the thermal paste but it made little difference. I think that the heat sink is not being clamped up close enough to the CPU die. (or am I just incompetent )

The 'lock down' mechanism seems a bit crappy.... a plastic cam arrangement. It's the Intel heat sink that came with the CPU.......

I'm going to try and get the sink to sit tighter on the die if possible. Could I have used too/much too little paste? I had a 'thin' but even layer.....

 

just make sure that all 4 pins are seated and look like the ends are separated a little on the back side of the board. This is best accomplished with the board out so that you can support the back.

 

When you change the heatsink compound, make sure you clean off all the old residue. This tends to harden with time and forms hard lumps which prevent the newer softer paste squashing down properly. You should aim for as thin a layer as you can whilst making it complete.

 

OK - success! :cool

After three more tries, I got the %$#@ plastic pins to engage properly with the mobo.

Temps are now down to 44'C idling with 2,300 rpm on the fan to a max of 53'C when in the middle of a game of Quake!

Thanks to all you for your help! It's much appreciated to be able to get some expert opinions on this stuff!

CVG

 

thats well within specs Game on

 

:major:major