Bad Capacitors or PSU Problem?

[saxman285]

Re: Bad Capacitors or PSU Problem?

but to have my old PSUs caps bad, AND the one i just bought?

.... i just have horrible luck? Earlier in the thread, people said my PSU caps looked fine...

and whats an ESR meter, and where do i get one?

[linuxguru]

Re: Bad Capacitors or PSU Problem?

OST can also go bad without visible bulging - it's worth recapping the entire bunch of OSTs with any of the recommended good caps. Pay attention to the caps near the Northbridge and DIMM sockets as well.

[stardreamer77]

Re: Bad Capacitors or PSU Problem?

hi saxman285,
i had a P4P800 deluxe, and i also got this problem b4, after check everythings...my solution is : change the "power switch" that one connect to the mb and casing! then , the problem gone!!!

and now , i got an other problem !! the pc always keep "restart" !!( continue restart!! even cant see the post screen.... ) also after 3 day of checking (it is killing me!!) .. the problem is the "reset switch wire" is broken!!...

so try unplug all the switch or led wire, then test it 1 by 1...

this is my experience, but i'm not sure my solution work in your case...
and sorry for my poor english....
hope this help.....

[starfury1]

Re: Bad Capacitors or PSU Problem?

guess this really is a sticky one, again not the expert here but here's my 2 cents worth

Since you have now ruled out the psu buy buying a new one.

If your old one was an enermax and it looks like my other one, mines been going for like 5 years (the computers been on for a couple of hrs (min) nearly every day since its been in)
near the bottom of this page


The caps look fine but as pointed out thats not a certainty that they are
(and there a fair chance they are not)

we are now back to MB or MB related card connector issue.
(maybe even a dry solder joint on the MB but others here are best to advise how likely that is)

Others have posted that the caps(some of them) can fall into the suspect list and you say its been in service for a while.

Recap might be the short answer.

If you are intending to keep this system for awhile a recap won't hurt anyway
(just got to hope it isn't a major MB problem if the recap don't work)

think it was willawake that said these can be a bit of a pain to recap so if you haven't done it , it might be best to get it done by TC or another forum member close to you if they care to offer you their services (err hope thats OK TC)
(you don't have a location on your tag)

I do have few questions thought

1) Does it ever happen when its cold (like 5 min after start) or is it always a couple of hours or so before it stops.

2 Does the system spend a lot of time powered up (like 4 Hrs plus each day)

3) how long has the system been running

you say that the problem has been getting progressively worse, guessing over the last few months
(if it is a failing cap it will only get worse)


lastly to explain ESR

think of that as "how well a capacitor pretends to be a piece of wire"
(this is a TOTAL LIE but hopefully gets the idea across)

So basically low esr caps you can think of as being like a jumper cables general purpose ones like speaker wire

So we want the capacitors to be "invisible" to the circuit and circuit operation, only act as a big storage bucket of power for the circuit so it can operate at its best.

The problem comes when the capacitor states to fail and starts acting as part of the circuit causing the circuit to malfunction
(becomes more like a resistor then a big bucket)

Again some what bending the truth.

ESR meters are not cheap things to buy you could buy a good MB for the price of some of them

willawake has a post of a production build version of this meter bobs esr meter kit
willawakes post

A bit on ESR and how bob come to make his meter here

there are other meters avail and some better some worse but all not that cheap.

There is a discussion thread somewhere here on building one too
(I have seen pre built's that probably use similar circuit going for over $200 US)

just a little info for u HTH

[saxman285]

Re: Bad Capacitors or PSU Problem?

think it was willawake that said these can be a bit of a pain to recap so if you haven't done it , it might be best to get it done by TC or another forum member close to you if they care to offer you their services (err hope thats OK TC)
(you don't have a location on your tag)

I'm in California

I do have few questions though

1) Does it ever happen when its cold (like 5 min after start) or is it always a couple of hours or so before it stops.

2 Does the system spend a lot of time powered up (like 4 Hrs plus each day)

3) how long has the system been running

you say that the problem has been getting progressively worse, guessing over the last few months
(if it is a failing cap it will only get worse)

1) Yes, it happens WHILE starting sometimes. So definitely regardless of cold or hot.

2) Yes, it spends a good amount of time powered up, but any decent computer should be able to handle that...

3) Computer born at the end of 2003 (if thats what you were asking)

Yes, its getting progressively worse. Now it is almost guaranteed that when i want to use it. It will shut off at least once when im trying to boot or immediately afterward, and then possibly again later while in use.

[Brian C]

Re: Bad Capacitors or PSU Problem?

Here are some suggestion from me :

1. If u have oscilloscope, please check the Vcore, Vdimm, 12V, 5V, 3.3V suuply waveform. Too large ripple voltage, especially under heavy load ( when loading windows, ruuning application), may trigger the protection circuit (shutdown).

2. It's hard to tell whether a non-bloating cap is a healty cap. You may need to recap the critical circuit like Dimm Voltage regulator, multiphase Vcore for cpu.

3. Please try new or other power supply (borrow from friend...). Some cheap power supply can easily out of regulation when some rails are lightly loaded due to bad cross-regulation.

!!! Merry Christmas !!!

[saxman285]

Re: Bad Capacitors or PSU Problem?

3. Please try new or other power supply (borrow from friend...). Some cheap power supply can easily out of regulation when some rails are lightly loaded due to bad cross-regulation.

This power supply IS brand new, and its not a cheap one. Its a Hiper Type R 580w PSU, but the system still shuts down at random times, be it during use, or during start up.

[davmax]

Re: Bad Capacitors or PSU Problem?

Keep focused on the Mobo. It seems that the power supply has been investigated enough. I have not picked up a photo of the mobo. This would help particularly if the shot details the caps around the VRM for the CPU and around the memory. As the problem is gradually getting worse and seems to be independent of temperature it does seem to suggest capacitor ageing. Causing a CPU supply ripple problem and crashing the CPU.

[saxman285]

Re: Bad Capacitors or PSU Problem?

There are pictures of the Mobo on page 2 of this thread.

[bgavin]

Re: Bad Capacitors or PSU Problem?

Where does one probe if the board won't power up at all? I assume there is a +5v point somewhere as a starting point... ?

[Rainbow]

Re: Bad Capacitors or PSU Problem?

Try shorting the PS_ON# signal (usually green wire) on the ATX connector to ground. If the PSU starts, then there is a problem in power-on circuit. If the PSU does not start, there is a short on the board.

[bgavin]

Re: Bad Capacitors or PSU Problem?

To clarify: I understand you to mean shorting the ATX signal to ground while plugged into the board.

I can start the PSU stand-alone using my PSU test tool. It starts up fine, spins the fans, etc. It is a known-good PSU.

[Rainbow]

Re: Bad Capacitors or PSU Problem?

Yes, while plugged into the board. Some boards will even start and run when powered up this way.

[Fizzycapola]

Re: Bad Capacitors or PSU Problem?

You should really cease or limit using this computer and power supply until problem can be resolved. Worsening problems eventually regulators will fuse inside causing ram, graphic card and CPU to be destroyed.

Any part that has been near a bad PC can give the same fault to new PC's.

It seems to me PC's increasingly are becoming the tool to keep the poor poorer, I for one would be quite wealthy without PC problems every few months and it doesn't seem to matter what parts I buy or how expensive.