Bad Capacitors or PSU Problem?

[saxman285]

My System:
Asus P4C800 Deluxe
Pentium III 3.0Ghz CPU revision C
2x 512MB Samsung PC3200 DDR
Enermax 350W PSU

For reference as to possible power problems, I run a 128MB GeForce FX 5900, a DVD-ROM, a CD-RW, and a 120GB HDD, and other miniscule components.

My problem is that my computer just randomly shuts off. Theres no blue screen, no restart, no shut down, it just turns off. I can be sitting and gaming, and the system will just turn off, or the computer can be sitting idle, running only low-demand background processes, and it will do the same thing. Sometimes it wont happen for weeks, and sometimes it will happen several times in a matter of an hour or two.

I was reading high temperatures at my motherboard and cpu about a year back, but i bought a couple extra case fans, and a new CPU fan, and it seemed to remedy the problem. So when this started becoming a major problem, i thought it could be more heat trouble, but sometimes it happens just minutes after booting (far too quickly to heat up to the point of failure).

I know having ample power is important for a computer, which is why I originally ordered a 430W PSU for this system. I was sent a 350W by mistake, and settled for a refund of the difference in price because i was assured that 350W was more than enough to power even high end computers. Now I was thinking maybe I made a mistake doing that, but someone told me it might be a problem with my capacitors instead, and directed me here.

I cant see any bulging or oozing on my Caps, but in searching the forums I see that some other people have had problems with capacitors on the same motherboard. Basically I am trying to figure out whether I need to buy a new, more powerful PSU, or if i should look into replacing my Caps. Could anybody give some helpful insight into which is most likely the problem im having?

Thanks in advance.

(And I kinda rushed through this since after writing it once, the computer shut off...... right before i posted. So if in my rush i made something unclear, and something needs clarifying, let me know and I will be happy to elaborate.)

[willawake]

Re: Bad Capacitors or PSU Problem?

i am running a 875 board, 2.8, 1gb, 3hdds, 2 optical, multiple fans on a 360w. but it is important to have a decent psu which is providing in the region of the quoted wattage to support that. enermax is probably ok.

that board has a terrible ost series for vcore. if they are not bulging then it is difficult to say if they are bad unless you had an esr meter to test them. One thing that comes to mind is that it also has a problem with the cpu retention mechanism that you can see includes a piece attached to the rear of the board that on some versions of the board causes excessive flexing and problematic issues like you are seeing.

is it correct that your problems occured before the psu purchase?

i am worried about the cpu retention mechanism, that is something that cannot be solved with recapping. perhaps it is not an issue in your case, reallyi dont know. i would recommend to replace the ost above the cpu and all other caps above 470uf on the board except for the chemicon 16v at the top of the board. its not a very easy board to recap though, the solder is stubborn in places, requires a hot iron.

[tiresias]

Re: Bad Capacitors or PSU Problem?

Welcome Saxman

Random 'loss of power'/shutting down can be quite a generic/nonspecific symptom, hence it is not always easy to, with certainty, exclude either PSU or motherboard (and its attached components) as the cause without testing them individually.

However, there are a couple of very quick and simple things you could check which would help at least exclude (not entirely, admittedly) the PSU as the source of the problems.

Once the machine has "randomly shut itself down":

1. Are you able to 'start it up' again by simply pressing the 'power button' (shorting the appropriate connectors on the motherboard)?

2. Is the PSU still supplying 5Vsb to the ATX connector?

Edit, for improved clarity: What I'm basically asking is: "is the PSU shutting itself down due to a short/overload/fault (which could implicate both it, or the motherboard, the wiring, or any other attached peripheral), or is the motherboard itself, for some reason (CPU overheat, BIOS issues etc.), setting PSON to high?"

[Per Hansson]

Re: Bad Capacitors or PSU Problem?

Your powersupply is more than enough for a system like that, with a guess I'd say your computer draws a maximum of 200-250w

It sounds likley that the capacitors in your powersupply are bad, if it is out of warranty pop the cover and have a look, however, be very careful and let it discharge fully, i.e. if it has an on off switch turn it off and press your computers start button so the capacitors discharge, you should see your LEDs blink and fans trying to spin 1/10th of a turn...

Also do not wear an antistatic wrist strap when working on high voltage equipment, the chock you will get when you are grounded will be much worse than if you are not grounded...

EDIT; tiresias was quicker with his post than me, do his error searching first, it is a very good way to figure out if you have badcaps too, because if your computer shutdowns due to badcaps, i.e. a voltage line out of range, the PSU will oftenly need 15-30 mins cooldown untill it "wants" to start again...

[willawake]

Re: Bad Capacitors or PSU Problem?

its a new psu though....

can you run some memtest86+ to give us some more clues to work with

[saxman285]

Re: Bad Capacitors or PSU Problem?

One thing that comes to mind is that it also has a problem with the cpu retention mechanism that you can see includes a piece attached to the rear of the board that on some versions of the board causes excessive flexing and problematic issues like you are seeing.

I did have a problem when i first ordered the board, which caused it be unable to POST stating "system has failed cpu test". I researched it a lot and found out about the problems with the retention mechanism, and instead of voiding my warranty by scratching down the solder like some suggested, i sent it back to Asus, who attempted once to fix it, then replaced it on a second attempt. Since i got the mobo replaced, however, i havent had that problem.

Are you able to 'start it up' again by simply pressing the 'power button' (shorting the appropriate connectors on the motherboard)?

Yes, as soon as it experiences a loss of power, i can immediately press the power button and the system will reboot as normal. Then it may be weeks before it shuts off again, or even a couple times will happen during or imediately after booting, but it usually happens within a day or two apart.

Is the PSU still supplying 5Vsb to the ATX connector?

i have no idea what that means.... guess im not that experienced in the really technical jargon of certain areas.

if your computer shutdowns due to badcaps, i.e. a voltage line out of range, the PSU will oftenly need 15-30 mins cooldown untill it "wants" to start again...

since i dont experience this "cooldown" time before it will power up again, does this rule out some things that i thought might have been problems?


edit: its not a new PSU, nor is the motherboard new. I purchased all the components at the end of 2003. I initially had problems with the motherboard as mentioned above, but that was resolved a long time ago. I had problems with heat, but that was also quite awhile ago. This shut down problem hasn't been present for the life of the system, but seems to be getting worse and worse, which leads me to believe that SOMETHING is failing, be it the PSU or the Caps, or something else. (maybe just because a component is reaching the limits of its lifespan? though i have had computers last far longer than 2+ years before....)

[willawake]

Re: Bad Capacitors or PSU Problem?

ok then it is the caps in the psu or mobo.

can you please do some memtest86+ http://www.memtest.org/ or http://www.memtest86.com/ for an hour or two and then advise if you see some errors.

check inside the psu for bulging caps. do not open the lid with the power connected to the psu, it is dangerous. otherwise it is ok.

post some pics if you like, it would help.

[saxman285]

Re: Bad Capacitors or PSU Problem?

Ok, well, upon the initial suggestions of the capacitors being a possible culprit to my problem, i thought it was just a motherboard thing. But at your advice, i opened up the PSU and checked it out, and saw huge clumps of what i first thought was dust, but upon closer inspection is actually a hardened white substance. Could be glue i guess, but i dunno why there'd be glue in there. I guess this would be the electrolyte (though the caps arent bulged at all). I took pictures, but my camera doesnt have a macro-focus, so it was hard to get them clear. I'm pretty sure after looking at the inside of the PSU that this is definitely the problem, but would still like some input, just in case im misreading.





larger versions and other pics

http://i7.photobucket.com/albums/y28.../DCP_1348a.jpg
http://i7.photobucket.com/albums/y28...5/DCP_1350.jpg
http://i7.photobucket.com/albums/y28.../DCP_1351a.jpg
http://i7.photobucket.com/albums/y28.../DCP_1355a.jpg

[Per Hansson]

Re: Bad Capacitors or PSU Problem?

Your caps are fine, the white stuff between the two large bulk caps is just what you thought, glue, there to prevent high frequency sound etc etc...

And the very blurry caps on the secondary side looks to be United Chemi-Con, if it is that is an excellent PSU! And yes, the stuff between the caps and the coil is glue there also, yet again to stop the coil from vibrating and creating coil noise...

Just inspect all caps on the secondary side and make sure that their tops are flat...

[saxman285]

Re: Bad Capacitors or PSU Problem?

hmmm... well all tops seem to be flat, and not bulged on both the PSU caps and those onthe mobo....

I guess i'll have to run those memtests when i get a chance, and maybe that will help....

[tiresias]

Re: Bad Capacitors or PSU Problem?

And the very blurry caps on the secondary side looks to be United Chemi-Con

The brown-maroon colour of the plastic sleeve can be deceiving, but these are without doubt "JP CE-TUL" caps, which are a ubiquitous feature within any not-too-old Enermax PSU.

Equally distinctive (but not shown in Saxman's photos) are the smaller black capacitors, which are invariably marked "JP CE-TUR". Whether TUR and TUL are actually different series, or a manifestation of the all-too-common 'Engrish' of swapping Ls for Rs and viceversa, I wouldn't know.

I guess i'll have to run those memtests when i get a chance

That can sometimes be useful - let us know how it works out.

While what you've told us can't entirely exclude the power supply as the cause of your problems, this is becoming more and more unlikely, as the 'shutdowns' occur in conjuction with the MB opening the PSON-GND connection, and not due to any obvious 'fault' with the PSU, which, from what we've seen, appears to be 'healthy'.

PS. If you have a multimeter, or voltmeter, a very useful test you could do further 'eliminate' your Enermax from the 'investigation' would be to measure the output voltages you're getting. Just bear in mind that ground wires are black...
Orange is +3.3, Red is +5, Yellow is +12, Blue is -12, Purple is also +5 (5Vsb)
White (if you have it) is -5, and Green is the ATX 'PSON', which should be +5 if the unit is off, and zero, if the unit is on.

[saxman285]

Re: Bad Capacitors or PSU Problem?

ok, im looking at www.memtest.org and just wondering how i should go about this. Will it create some sort of log that i can post here to get some feedback? or will i need to know how to interpret what it shows me?

[willawake]

Re: Bad Capacitors or PSU Problem?

i forgot how it works. it must create a log.

just tell us if there are errors detected. test both sticks and then each one individually

[Per Hansson]

Re: Bad Capacitors or PSU Problem?

You just run it from a floppy or bootable CD (ISO)

If there are errors they will be listed in red, if there are errors no need to write down address or anything, just that there are errors...

And no, there will be no logfiles

[PeteS in CA]

Re: Bad Capacitors or PSU Problem?

Those O/P caps probably aren't UCC, as their vent pattern usually looks like a "Y" with equal length legs spaced 120 degrees apart. Another purpose of the glue or RTV is to improve mechanical reliability under shock and vibration.

[tiresias]

Re: Bad Capacitors or PSU Problem?

Those O/P caps probably aren't UCC, as their vent pattern usually looks like a "Y" with equal length legs spaced 120 degrees apart.

No indeed, as I said in my earlier post , they're the usual "JP CE-TUL" that one finds essentially everywhere (save the input caps) in Enermax PSUs.

[saxman285]

Re: Bad Capacitors or PSU Problem?

Sorry for the delayed reply, i had a hard time getting the memtest bootdisk to burn properly (and my floppy drive has been messed up forever).

I ran memtest86+ 1.65 for about 3.5 hours and came up with no errors..... im considering that a bad thing only because it still gives no clues as to what the problem with my computer is.

[RJARRRPCGP]

Re: Bad Capacitors or PSU Problem?

Run it for at least 18 hours.

[saxman285]

Re: Bad Capacitors or PSU Problem?

18 hours..... you've got to be joking me.

This is gonna show me why my computer shuts off every couple hours, and yet its gonna take 18 to even show an error?

Is that really necessary?

[tiresias]

Re: Bad Capacitors or PSU Problem?

18 hours..... you've got to be joking me.

This is gonna show me why my computer shuts off every couple hours, and yet its gonna take 18 to even show an error?

Is that really necessary?

Hi Saxman,

Should you bother with the memtest at this point? In my opinion, no. In fact, I have read nothing in this thread whatsoever that suggests that your problems be DIMM-related!

My advice would be as follows:

1. If possible, try to definitely exclude your power supply as the source of the shutdowns by running your machine, a day or so, with another PSU. Does the problem still occur? Then you know your Enermax is working fine.

2. Does the issue worsen, even in part, with increased CPU loading/heat/power consumption? This is easily tested. Run "BURNK7.exe", included in http://pages.sbcglobal.net/redelm/cpub4gx.zip . This brutal little tool will, for as long as you let it run, make your CPU use far more power than any other application I've ever seen, including Prime95.

3. Try also BURNMMX.exe from the same package - this is an endlessly looping and intense memory (and hence memory controller) test. (Memtest's test 5 is actually based on this)

4. If neither of these result in a blue screen or shutdown, and you know the PSU is good, then - barring some wonky expansion card causing an intermittent short -, at least you've narrowed the problem down to a single, replaceable part, the motherboard.