PC failure; suspect CPU, but have acrid smell.

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Froo
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PC failure; suspect CPU, but have acrid smell.

Post by Froo »

Hey everyone. The PC my wife uses died a couple weeks ago, so I set her up with the 'later' one I built.
This is the sequence of events.

1) System would freeze: disk light stayed on, screen was black.
A system reboot would get it going again.
This went on for several weeks.

2) System would freeze. A reboot would allow the system to be on
for a few minutes, then a system freeze would occur.
Cranked up the CPU cooling fan speed, and rebooted.
This worked for a couple weeks.

3) Now, system will no longer boot.
I smell a nasty acrid smell, like fried electronics.

Here's my question. This seems to point to a fried CPU, but, will the CPU alone
deliver that 'fried electronics' smell? I believe I built this system around the year
2000, so it's 11 years old, approximately. So, I don't want to spend much money
trying to repair it. See, it could be the CPU ($10), or the power supply ($40), or the mobo ($50).
If it's just the CPU, no problem. But, I'd buy a CPU only if I knew, that the CPU itself
could give off that smell if it were fried.

I could reuse some parts (hard drives, cd/dvd drives), and sell others (video card, memory).

So what do you think? If the CPU were fried, could it give off that smell? Like I said,
the symptoms point to a CPU failure, as described above. But the smell makes me doubt,
that the CPU is the only problem. If it's not the only problem, to heck with it. But if it is, I
can save the system for $10.

Thanks!

Froo
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GSH
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Re: PC failure; suspect CPU, but have acrid smell.

Post by GSH »

Something that old? I'd suspect bad capacitors. See if there are any capacitors on the motherboard with puffy tops like the second picture in http://techreport.com/discussions.x/21360. If it's a bad cap on the MB, then it's probably time to replace the whole MB unless you're REALLY handy with a soldering iron.

-- GSH
Froo
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Froo »

Thanks GSH.
I'll check the capacitors near the CPU.
I don't know if it is worth the time, money, and effort to fix it.
If it's a $10 job then it's probably worth it. But more than that, I don't think so.
I used to upgrade and build our home systems but around the time SATA drives
were coming around, I decided to wait til a system 'died' before another rebuild.
Perhaps that time is now. I've seen some pretty nice barebones kits on newegg
recently. It's just a shame though, to see this one go.

Froo
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Red Devil
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Red Devil »

shoot it.
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Psychedelic Rhino
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Psychedelic Rhino »

PSU
Froo
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Froo »

Yeah I am worried about the PSU as well.
I could get a PSU tester.
But, the original symptoms point to the CPU/mobo:
system freezes; reboots worked initially, turning up the fan speed kept it running awhile.
Another person suggested that the heat transfer paste between the CPU and
heat sink would cause that smell when it overheated.

I think I will try replacing the CPU; if that does not solve it, then it's done.

Thanks everyone.
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Red Devil
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Red Devil »

some towns have places where you can get used computer equipment, so try there first to save some bucks.
Froo
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Froo »

Well, I do see 3 capacitors with raised tops; I can run my finger over the
top and tell the difference between these and the others.
Froo
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Froo »

Actually, there are 4.
I google'd: motherboard capacitor. Found a pretty interesting Wikipedia page about this.

http://en.wikipedia.org/wiki/Capacitor_plague

The symptoms, and things I did to get the computer going, are exactly what are described in the middle of the page.
If I am going to take this computer apart, I may as well do the power supply too. What the hey, what have I got to lose?
Nothing really. In fact, come to think of it, I recall dreading having to meddle with this machine in years past. I had
to doodle with the hard drive cable connection at the mobo to get it to boot sometimes. It's been ok for a few years
since I stopped meddling with it. It'd be pretty cool if I could get it working again. And if I fry it more, oh well. :ugeek:
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Psychedelic Rhino
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Psychedelic Rhino »

The reason I suggest a PSU might be the issue is because they can mimic many other issues, and it never hurts to replace it if the PC is old and you plan on keeping it a while longer.
Froo
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Froo »

Thanks Psychedelic Rhino.
That's on the list of possibilities as well.
And that's the thing. If it turns out, there are multiple problems:
PSU, CPU, capacitors, motherboard, then it may not be a wise
decision to replace all that.
I could use a PSU tester to determine if it is faulty. I'd have to get one though,
or borrow one.
One thing is certain; if a capacitor with a puffed up lid will always lead to failure eventually,
then those capacitors would have to be replaced.
I'm just glad this didn't happen the first couple months I owned the thing, back in 2000 or so.
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Zero Angel »

Blown capacitors on the motherboard are bad news -- I doubt that the CPU is the problem at all, but it is possible that the problem originated from the PSU. If you are really curious, then crack open the PSU and check for blown capacitors there too -- if the PSU has blown capacitors or otherwise feeds 'dirty' or insufficient power to your motherboard and components then it can shorten the life of them considerably (hence it is always a bad idea to buy the cheapest PSU you can get)

Sounds like it's time to replace the barebones setup on your PC (PSU, Motherboard, CPU, RAM). The onboard video that you can get with many motherboards manufactured this year will probably be better than any videocard made more than 5 years ago.
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Red Devil
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Red Devil »

stick a UPS between the PC and the wall receptacle to filter power spikes, too.
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Re: PC failure; suspect CPU, but have acrid smell.

Post by MrTwosheds »

Then place the whole thing in a SKIP and buy a new one. You know you want to :)
Froo
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Re: PC failure; suspect CPU, but have acrid smell.

Post by Froo »

heh yeah I'd definitely like to buy a new system. Maybe keep this system around for spare parts.
But I'll have to wait awhile on that if I choose to go that route.
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