Power supply

Swamp Donkey

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My son's old computer conked out yesterday, turned out to be the power supply. It was an old mini type case, so it was easier to replace the case and the power supply. It had some tiny ass 200w PS originally, which I replaced with a 500w. The 500w I bought probably 3 years ago was the one that died. However the midrange graphics card I added (960 or 1060, I forget) actually called for like 600w, so I added a 750 this time. The 500 didn't really fit in the old mini case and I had to let the DVD writer stick out the front of the case 1-2 inches to shoehorn it in there. New case meant plenty of room of course.

So, what kills an old PS usually? Doing an autopsy on the PS, I don't see anything obvious. No smoked components, no wires, no obvious solder issues or overheating etc. Fan spins, though I didn't put it to power yet to see if it works. It was Chinese crap of course and I couldn't help but notice that the computer warehouse place that sold me the old one no longer carries this brand.

Can it just be overuse, running at max all the time to feed that graphics card? Or more likely some component Im not seeing just quickly eyeballing the board in the PS? Just being nosy here and I know there are some smart geeks on this board.
 

Concrete Helmet

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My son's old computer conked out yesterday, turned out to be the power supply. It was an old mini type case, so it was easier to replace the case and the power supply. It had some tiny ass 200w PS originally, which I replaced with a 500w. The 500w I bought probably 3 years ago was the one that died. However the midrange graphics card I added (960 or 1060, I forget) actually called for like 600w, so I added a 750 this time. The 500 didn't really fit in the old mini case and I had to let the DVD writer stick out the front of the case 1-2 inches to shoehorn it in there. New case meant plenty of room of course.

So, what kills an old PS usually? Doing an autopsy on the PS, I don't see anything obvious. No smoked components, no wires, no obvious solder issues or overheating etc. Fan spins, though I didn't put it to power yet to see if it works. It was Chinese crap of course and I couldn't help but notice that the computer warehouse place that sold me the old one no longer carries this brand.

Can it just be overuse, running at max all the time to feed that graphics card? Or more likely some component Im not seeing just quickly eyeballing the board in the PS? Just being nosy here and I know there are some smart geeks on this board.
You lost me at the word computer.....sorry, you really wouldn't want my help.....I thought that's what kids were for...
 

ThreatMatrix

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Transformer insulation breaks down. Dielectric breaks down. Connections within the ICs themselves come loose. Particurly on something that experiences a lot of heat and a lot of cycling. Semiconductors experience migration of the materials they are made of. Quality of the electronic components do vary. I.e. You can by cheap caps and you can buy expensive caps and there's a reason for the difference in price.
I've spec'd a lot of electronic components in my career. They all have MTBF ratings. Put it all together and the component is only as good as the weakest link.
TL:DR Heat, cycling, quality.
 

Detroitgator

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Transformer insulation breaks down. Dielectric breaks down. Connections within the ICs themselves come loose. Particurly on something that experiences a lot of heat and a lot of cycling. Semiconductors experience migration of the materials they are made of. Quality of the electronic components do vary. I.e. You can by cheap caps and you can buy expensive caps and there's a reason for the difference in price.
I've spec'd a lot of electronic components in my career. They all have MTBF ratings. Put it all together and the component is only as good as the weakest link.
TL:DR Heat, cycling, quality.
That’s what I learned from my link for sure
 

ThreatMatrix

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That’s what I learned from my link for sure
Which doesn't approach 35 years of experience. The point is that there are more things that can go wrong than you can hope to see. It's generally a pretty lucky day if I can open something up and actually see the failed component.
 

Swamp Donkey

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Which doesn't approach 35 years of experience. The point is that there are more things that can go wrong than you can hope to see. It's generally a pretty lucky day if I can open something up and actually see the failed component.
Thanks.

I do think I see a hint of overheating (slightly discolored) on the board around the IC. I may screw around w the components later, remove them for the hell of it and see if there is more evidence.
 

ThreatMatrix

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Thanks.

I do think I see a hint of overheating (slightly discolored) on the board around the IC. I may screw around w the components later, remove them for the hell of it and see if there is more evidence.

If you can you can try to replace the component. But that involves being able to read the markings in order to replace it. Also, depending what it is you may have one helluva time desoldering and resoldering.
Post a pic of what you think it is.

I think you did the right thing though. If you need 600W buy 750W. Consumer stuff isn’t derated by much. So if your continuously pushing 600W through a 600W PS you ARE going to face an early death.
 

grengadgy

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I can't believe that you are even f vcking with a power supply Have you checked any voltages? Regulators usually go bad.
 

ThreatMatrix

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I wouldn’t bother with anything without a schematic. You’re just guessing with a low likely hood of success.
Other than an obviously bulging cap there’s no telling what’s happened. If a regulator went bad I’d wonder why. I’d also wonder what else got toasted. Bad traces within the PCB are going to be impossible to find.

I’ve designed power supplies as well as other electronics. Even with an intimate knowledge of how it works, equipment worth 10s of thousands of dollars and a lab tech to solder components it can take anywhere from minutes to days to figure out what went wrong.

Of course you can always get lucky. I’ll open up anything that doesn’t work. If I see an obviously bad component and it looks easy to replace I’ll do it but that rarely happens.
 

Swamp Donkey

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I can't believe that you are even f vcking with a power supply Have you checked any voltages? Regulators usually go bad.
Im not. I replaced it immediately.

I just wanted to know, because I'm an idiot like that.

And maybe harvest components. Put some in my ziplock back of other resistors and components. For future projects. That have never materialized in decades.

Say, you don't any old HDD working or power on LEDs, do you? :lmao2:
 
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grengadgy

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Im not. I replaced it immediately.

I just wanted to know, because I'm an idiot like that.

And maybe harvest components. Put some in my ziplock back of other resistors and components. For future projects. That have never materialized in decades.

Say, you don't any old HDD working or power on LEDs, do you? :lmoa2:
A couple of years ago I rent a large rolloff dumpster and sh*t canned all of my old computer parts and cases. Only filled up half of it and that was kind of disappointing.
 

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