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HELP! PC just died....


Standard Member
A few days ago I got a windows (XP) error message relating to my HD, no problems since then until I noticed a electrical overheating type smell from my power supply.

This all seemed to go away with no problems. I was concerned about the HD so I ran a diagnostic program for the HD, left the PC to it, when I returned it had totally died.

I have today bought a new power supply, and replaced the old one, but the problem persists. USB devices (wireless mouse) have a LED illuminated so some power is getting through the motherboard. WHen I power the PC up the processeor fan spins for a fraction of a second and then nothing.

Is this likely to be the motherboard, or the processor, or hard drive. The monitor etc will not power at all...

3.4Ghz P4, 1Gb RAM, media centre edition, 16months old.

Any help would be greatly recieved.

Thanks in advance. :thumbsup:

Pack Dude

Active Member
Did the fans spin the same why on the old power supply? A short somewhere like a plug being put in backwards will make the power supplys short circuit protection cut the power just as the fans start up.

Try unplugging as much as you can (like the harddrives and floppy) to see if you can get into the BIOS.

Is the case speaker connected to the motherboard? With a bit of luck there will be some bleeps which is a code for different problems.


Active Member
I would be tempted to say it could be either the Motherboard or the Processor. When powered on check for the burning smell to see if it comes for anywhere else other than the PSU. I have had a few motherboards where component on the board have started smoldering! It seemed like it was the PSU but it was the Motherboard. It could also be the CPU, if you are getting power but no POST response it could also be the cpu.

Hope this helps.


Standard Member
Thanks for your help, there is no beep at all when the PC is switched on, there must be some power getting through from the PSU as the USB devices have a LED lit up.

When the fan turns for a split second (this doesn't happen every time) its as though a slight surge goes through the motherboard, but thats all. My guess would be the motherboard. I am totally unable to get anywhere near the BIOS, and get the same when I unplug all components into the mobo.

Is there a check I can to do to see which component it is (distinguish between CPU and mobo)? As I've 2 PSUs that do the same thing and one is brand new it is safe to say that its not that. Unfortunately my old PC is AMD and will not run my P4, and its hard drives are not SATA so cant check them.

Is it a safe assumption that its either my mobo, processor and not my HD?

Thanks again for the help, don't really want to waste money on a replacemnet mobo (like I did with the PSU it seems) if its the processor or vice versa....


Pack Dude

Active Member
I dont know of anyway of testing the mobo or chip apart from trying them in other hardware. Maybe someone will come along with better advice.

The only thing i can think of is stripping down the PC to only the mobo, CPU and RAM (you dont need any harddrive connected to get to the BIOS). Turn it on and see if the fans spin if they do try it with the video card in and so on till you find the porblem.

You said you could smell some type of electrical overheating, have a look at the mobo to see if any components are burnt.

Good luck.


Standard Member
Thanks pac man, I'll try it that. I suspect I'll still have no power with only the CPU, mobo and RAM connected, then won't know which of those it is! :rolleyes:

Do you think the error message relating to the HD could be actually caused by the mobo? I cant seem to see any dodgy components so am at a bit of a loss. Could a faulty HD have caused this in the first place?

Do you think a mobile repair man would be able to distinguish, or would that be a waste of time/money?

thanks again, much appreciated....

Paul Shirley

Active Member
PC's can show this instant shutdown symptom with CPU faults. Sometime reseating the CPU in its socket is enough to fix the problem.

Unfortunately that burning smell probably means something more serious is wrong and its the short circuit protection kicking in. I've seen hard drives with actually burnt circuits, that could trip the circuit protection. Best bet is the earlier advice, start with CPU+mboard+RAM, reseat the CPU&RAM and make sure the CPU heatsink is properly in place (though thermal shutdown normally takes a few seconds to kick in). Add back till it stops working.

If it turns out to be a bad mboard its probably cheaper to just replace it than attempt a repair.


Standard Member
Thanks, having never reseated the CPU; is it a difficult process? I'm aware I'll need some thermal grease - any tips/recommendations? (P4 550 3.40GHz chip, gigabyte GA-81915 mobo).


Paul Shirley

Active Member
Reseating is simple, just lift the locking lever on the ZIF socket, wiggle the processor a little and push very gently down, then relock it. Basically your just making sure all the pins are inserted fully. With vertically mounted boards and large heatsinks they can sometimes gradually drift out enough to cause problems.

The only complication is the heatsink, you'll need to remove it first, so try this after stripping down to CPU+RAM if that doesn't resolve your problem.


Standard Member
I've tried only the RAM/CPU and motherboard connected to the PSU now and I'm still unable to access the BIOS, I've also tried this with an alternate power supply. Whether or not the HD has caused this problem in the first place, something else is obviously not right.

I've managed to access the processor by removing the heatsink and opened the ZIF (?) socket. On the processor (P4 3.4Ghz prescott) there only seems to be contact pads as opposed to pins as previously described. The ZIF socket seems to fit pretty tightly so I guess (hope!) the CPU is OK and the mobo is the problem.

I'm unable to try the reseated CPU at the moment as I'm awaiting some Artic Silver, but think this will be OK.

Does anyone else have any thoughts before I fork out for a new mothorboard?

Thanks in advance....


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