Not quite, but almost same - maybe PSU monitoring circuit is FSP 3528 (instead 3529 on THN series) and some minor differences.

Mates, we’ve already been bragging about our P..Pi..Pin.. PSU`s. 😀
But no one has posted anything about this topic yet.
For example, I use my retrorig for a year
- Pentium 3S (30 W) + Radeon 9800 (60 W)~90W
- Athlon XP (60 W) + Radeon 9600 (30 W)~90W
- an early Pentium 4 motherboard~90W
with a modern power supply—it’s currently on sale; here’s the link.

Can you send the link again? It's missing in the post and I am intrigued.

So ‘no one’ 🙁

I opened up my Enermax 300W PSU out of curiosity. Capacitors seem to be fine, but I don't recognize their brand.

I guess the 5V rail is fine, as well.

CharlieFoxtrot wrote on Yesterday, 05:11:

I don’t understand your long posts, where you sort of try to disagree with me, but then you agree with me. I mean, you don’t seem to trust those PSUs either, when you always inspect them and test them. Of course it goes without saying, that caps can and do fail without any visible signs and I’ve encountered countless of such capacitors. Also, caps that have been sitting unused for long periods of time can start to fail rapidly after they are re-energized as the chemistry has changed. Again, no external visible signs and they can even give proper in spec readings to your esr meter at first.

Anyways, you do you. Changing caps to these old PSUs is like a 30-60 min of extremely simple work and parts cost is probably 10€ at best, so I really don’t see a reason why I would want to use these old PSUs with capacitors that are absolutely nearing their end of life. Changing caps to motherboards of this era is generally much more time consuming due to multilayer PCBs.

You are welcome to do the opposite and plug whatever you like to your equipment. But to me it is a no brainer to spend few beans and a bit of time to get rid of the old unreliable caps while I would open and clean the PSU in any case and thus have a reliably working PSU for years to come.

I guess he's saying that you worry too much. 😀

And sure, if you have the skill, time and equipment to change capacitors to PSUs just to be sure even when it probably is unnecessary, sure, go for it. But not everybody has those.

Caesum wrote on Yesterday, 15:16:

Can you send the link again? It's missing in the post and I am intrigued.

Everyone of us, including shevalier is looking for that link.

Mike_ wrote on Yesterday, 16:31:

I opened up my Enermax 300W PSU out of curiosity. Capacitors seem to be fine, but I don't recognize their brand.

Does it say P CE-TUR or TUL? If so, the manufacturer is CEC International. It is Teapo/Capxon level stuff, that is they sometimes seem to last, sometimes not and are thus unreliable low quality junk. Very common brand with 2000s PSUs with Teapo, I always change both without thinking. At least many Seasonic PSUs are also often full of these. As quality brands wanted to save a buck, they opted these, Fuhjyy, Tayeh and bunch of other low quality trash and ruined their otherwise fine designs.

I guess he's saying that you worry too much. 😀

And sure, if you have the skill, time and equipment to change capacitors to PSUs just to be sure even when it probably is unnecessary, sure, go for it. But not everybody has those.

I sort of get it if you don’t have soldering iron (although I find it odd that in this hobby people don’t want to repair stuff), but if you do, changing caps to these PSUs is probably the easiest soldering you can do. And time? Isn’t this supposed to be a hobby, but you can’t spare half an hour or hour to repair your gear!? Well, I guess most of the time is spent on writing overly long forum posts 🤣

AlexZ wrote on Yesterday, 16:37:

Caesum wrote on Yesterday, 15:16:

Can you send the link again? It's missing in the post and I am intrigued.

Everyone of us, including shevalier is looking for that link.

If it’s the the Sеаsonic whith ‘Adamantium’ rating , or the ‘Anobtanium’ one – I’ll give it a miss.
1-2k$ is just too cool.

Mike_ wrote on Yesterday, 16:31:

I guess the 5V rail is fine, as well. https://www.vogons.org/download/file.php?id=241009&mode=view […]
Show full quote

I guess the 5V rail is fine, as well.

https://www.cybenetics.com/attachs/52.pdf
page 34
If measurements are taken with no load, this does not indicate anything.
However, if ‘The output ripple and noise requirements listed in Table 4-6 shall be met throughout
the load ranges specified for the appropriate form factor and under all input voltage’, then the power supply unit is in excellent condition.

I also opened a Fortron 350W PSU and this thing is definitely not fine. I guess I'll just throw it away, as it's a pretty generic PSU to begin with.

CharlieFoxtrot wrote on Yesterday, 17:10:

Does it say P CE-TUR or TUL? If so, the manufacturer is CEC International. It is Teapo/Capxon level stuff, that is they sometimes seem to last, sometimes not and are thus unreliable low quality junk. Very common brand with 2000s PSUs with Teapo, I always change both without thinking. At least many Seasonic PSUs are also often full of these. As quality brands wanted to save a buck, they opted these, Fuhjyy, Tayeh and bunch of other low quality trash and ruined their otherwise fine designs

Yes, it does seem to say P CE-TUR. I guess this one would be worth the effort to recap if needed, as Enermax was a quality brand at the time.

CharlieFoxtrot wrote on Yesterday, 17:10:

I sort of get it if you don’t have soldering iron (although I find it odd that in this hobby people don’t want to repair stuff), but if you do, changing caps to these PSUs is probably the easiest soldering you can do. And time? Isn’t this supposed to be a hobby, but you can’t spare half an hour or hour to repair your gear!? Well, I guess most of the time is spent on writing overly long forum posts 🤣

Half an hour to hour sounds very optimistic to me. 😁 Also, while it's technically easier than recapping a motherboard, it's still AC equipment so I wouldn't recommend fixing it yourself to a beginner.

shevalier wrote on Yesterday, 17:22:

https://www.cybenetics.com/attachs/52.pdf page 34 If measurements are taken with no load, this does not indicate anything. Howev […]
Show full quote

https://www.cybenetics.com/attachs/52.pdf
page 34
If measurements are taken with no load, this does not indicate anything.
However, if ‘The output ripple and noise requirements listed in Table 4-6 shall be met throughout
the load ranges specified for the appropriate form factor and under all input voltage’, then the power supply unit is in excellent condition.

I was using Gigabyte GA-7ZXE and Athlon XP 2200+ as load, so there was a load, but not one close to maximum.

Mike_ wrote on Yesterday, 17:40:

Yes, it does seem to say P CE-TUR. I guess this one would be worth the effort to recap if needed, as Enermax was a quality brand at the time.

Yes, those are otherwise fine PSUs. I have few early 2000s Enermax PSUs in use and I can’t complain. Overall design and build quality, at least to me, feels very solid.

Half an hour to hour sound very optimistic to me. 😁 Also, while it's technically easier than recapping a motherboard,

In an hour, even a relatively beginner changes quite many capacitors. If you really are so tight on time with your hobby, then just change the main voltage rail filtering caps and leave all the smaller ones from the regulation and protection circuits with original caps. Your situation improves a lot as those are the caps that are most stressed and likely to go. The small caps around the PCB are most likely fine, just like in the motherboards as the current flow and heat generation is very low through them. There are roughly half a dozen or so of these large filter caps in these PSUs. That is not a lot.

it's still AC equipment so I wouldn't recommend fixing it yourself to a beginner.

Didn’t you guys say that I worry too much about mains equipment? If I remember correctly, someone said that mains voltage isn’t even actually high voltage and the other guy said that a fire in your PSU isn’t that big of a deal? So why so worry now? 😉

Stay on the secondary side and leave the stuff alone on the primary and I can’t see how your PSU can turn to more unsafe after you’ve removed your shitty old secondary caps from it and replaced them with new reliable ones. After the work, attach a load to the PSU, test it for a good while while you keep an eye on it. If there will be magic smoke escaping because you’ve screwed up something, it most likely happens in the first second you power the PSU on, but it doesn’t harm to run it for a some time under a load and grab a beer or coffee while doing so.

appiah4 wrote on Yesterday, 11:58:

Mine is the ATX-400PNF, so not quite the same model. We will see..

Literally the same chassis with some very minor differences.

The weakest part is probably the shitty quality ball bearing fan.

Mike_ wrote on Yesterday, 17:40:

I also opened a Fortron 350W PSU and this thing is definitely not fine. I guess I'll just throw it away, as it's a pretty generic PSU to begin with.

In the FSP on this platform, the supervisor is located on a small vertical board positioned perpendicular to the vertical board housing the PWM controller.
Under the fan control board
If the board with the supervisor is present, it’s an excellent PSU.
If not (no voltage monitoring, only general short-circuit protection based on maximum power), then it’s just so-so.
A good source of spare parts.

I was using Gigabyte GA-7ZXE and Athlon XP 2200+ as load, so there was a load, but not one close to maximum.

In that case, it’s in excellent condition, without a doubt.

I tried running my 400w FSP with just a hard drive attached and it started making high pitched squealing sounds like a dying rat...

Is it because the load was too low maybe? I was too scared to plug it into a real board to try it..

Well gentlemen (and ladies?), I'm glad to see this thread has spawned some good PSU discussion and curiosity by people to open up and post picture of their PSUs.
I've actually had this idea in my head for quite a while now to start a topic like this, where we can post picture of PSUs so that more people can see what is good and what isn't by example. But I suppose this thread appears to be doing this now. GOOD! 😀

CharlieFoxtrot wrote on Yesterday, 05:11:

I don’t understand your long posts, where you sort of try to disagree with me, but then you agree with me.

Yes, that's because I agree with you on some topics and disagree on others. 😀

CharlieFoxtrot wrote on Yesterday, 05:11:

I mean, you don’t seem to trust those PSUs either, when you always inspect them and test them. Of course it goes without saying, that caps can and do fail without any visible signs and I’ve encountered countless of such capacitors. Also, caps that have been sitting unused for long periods of time can start to fail rapidly after they are re-energized as the chemistry has changed. Again, no external visible signs and they can even give proper in spec readings to your esr meter at first.

OK, so to continue with my agree & disagree trend here... 🤣

Yes, I don't trust just about anything I get 2nd hand (and I buy electronics 2nd hand almost exclusively... or so for the last 15+ years.)

I know caps can be bad without showing any visible signs... and again, this is where I rely on experience to try and tell what/which caps should be replaced at minimum (if any.) But whether or not I will change the capacitors mostly depends on what brand they are and how likely they are to fail in the specific PSU. I'm not claiming this is the "ultimate" way everyone should do it. But the reason I do it this way is because I've reworked/handled enough PSUs over the years to have a good idea of what to expect.

What I disagree with you on is that you seem to treat all capacitors the same exact way, like they are a ticking alarm clock or food with an expiry date.
YES, electrolytic capacitors are -wearable- components and they do degrade over time.
But NO, they don't all degrade the same way and there is no magic number of years after which they are no longer suitable for use, be it sitting on a shelf or having been in active use. The "shelf life" in datasheets is only a -minimum- number of hours the manufacturer can guarantee for said capacitors. But there is no limit or maximum or "expires after" XX hours. Likewise, the "life time" of electrolytic capacitors is typically stated as X hours @ full rated voltage and the maximum allowable operating temperature - and this is, again, the -minimum- guaranteed life by the manufacturer. If you lower the operating voltage or temperature (or both), the lifetime increases quite a bit. Generally, for every 10C reduction below the maximum allowable temperature, the expected cap lifetime should double. So a 2000-hour 105C -rated cap running at at full rated voltage and 95C will have a minimum guaranteed lifetime of 4000 hours. Lower that to 85C, and we are approximately at 1 full year of 24/7 use (a little more than 8k hours). Lower the maximum operating voltage below that of the cap's rating, and the lifetime increases again.
Now that theory above is all nice in words. But in practice, the real question is which capacitors brands will stand by the numbers on their datasheets. IME, that would be the "big 5" Japanese brands: Rubycon, Nichicon, United Chemicon, Matsushita/Panasonic, and Sanyo (now Suncon). Everything else is a maybe.
And this is why I stand by my argument that quality-made electrolytic caps can still be fine to use, even after many years of sitting around or in active use. So long as the equipment has not been mistreated physically (mostly just overheated), big chances are everything will be OK.

CharlieFoxtrot wrote on Yesterday, 05:11:

Anyways, you do you. Changing caps to these old PSUs is like a 30-60 min of extremely simple work and parts cost is probably 10€ at best, so I really don’t see a reason why I would want to use these old PSUs with capacitors that are absolutely nearing their end of life. Changing caps to motherboards of this era is generally much more time consuming due to multilayer PCBs.

You are welcome to do the opposite and plug whatever you like to your equipment. But to me it is a no brainer to spend few beans and a bit of time to get rid of the old unreliable caps while I would open and clean the PSU in any case and thus have a reliably working PSU for years to come.

Oh, I completely agree with you here.

It is indeed a mystery to me as well how people manage to do anything in this hobby without knowing how to do some basic soldering - throw away and buy something else until stuff works, I suppose.

I don't know where you got the impression that I don't want people to recap their PSUs. In fact, I usually encourage it.
That said, all of my earlier posts were in consideration of the O/P's request that he/she did not want to do any soldering, so my suggestions were made in an attempt to comply with this to at least some extent.

Now, as for my own stuff/PSUs: really the reason I don't fully and absolutely recap everything is because 1) I often run out of stock on my capacitors and 2) it would be "kind of" a waste to recap something that I might just use a few times a year (if even that.) Also, having experience with recapping various PSUs for many years usually allows me to have a good idea of what (cap(s)) are more likely to fail and what aren't. As such, this is why my general procedure is more along these lines:

a) Any Japanese caps are left alone / *not* replaced. The only exception is if there are series in there that are well-known to be problematic (e.g. Nichicon PR). And for PSUs with APFC, the primary cap gets pulled out and checked for capacitance, ESR, and leakage current under full voltage (despite being a Japanese brand), because as I mentioned, the APFC circuit in some PSUs really runs them too hard.

b) If the caps are not from a reliable Japanese brand but are a known / generally well-received "2nd" tier stuff like Teapo, OST, Samxon, CapXon, CEC-holdings (PCE-TUR/TUL/TUK/etc.), Lelon, Ltec, and Su'scon... I might replace them or I might not. And if I replace any, it might be all or just a few in what I think would be "key" / high-stress locations. It all depends where the PSU will be going. Generally, if I am fixing it for someone and I know it will see lots of use, I'll more than likely do a full or nearly full recap. If it will be just a spare unit for myself that won't see much use or be stressed to the max, I'll typically leave most of the capacitors as-is and only change anything that might just seem necessary to establish a decent baseline for the reliability. And of course, there's everything in between these two scenarios. So it all depends.

shevalier wrote on Yesterday, 06:22:

At first, my Chieftec CFT650-CS14 power supply started behaving like this.
A quick search online showed that this is a common problem.

Details

https://forum.corsair.com/forums/topic/123146 … it-now-working/
There’s even a completely useless video demonstrating how not to do it.
https://www.youtube.com/watch?v=4X3nBE0Ys8E
Then my search led me to a forum for power supply repair experts, which describes a very simple and straightforward repair procedure
- press the power button. If the output voltages appear but there is no PowerGood signal
- check the voltage across the main primary capacitor. If it is not within the range of 377–383 V, then
-- replace the Champion CX03x chip with jumpers (its literal description: ‘No-load power consumption can be reduced to ~180 mW for use in EPA/Climate Saver applications’)
-- check the high-voltage divider. The problem may also lie in the glue under the high-resistance resistors. Remove it.

https://www.eevblog.com/forum/projects/possib … rk-as-expected/

Thank you!
Ah, so it's the guys at EEVblog, cool. I've been contemplating often over the years whether I should join that place too. But the last few years, my presence online has been steadily diminishing.
I'll take a read at it later tonight... though I do get a good idea from what is happening based on your description.

AlexZ wrote on Yesterday, 07:11:

Let's have a look inside

Glad you showed it. 😀
Yeah, that thing ain't doing 30 Amps on the 5V rail. You can see why in this shot:
download/file.php?id=240956&mode=view
See those three rectifiers on the secondary heatsink? They are all in TO-220 package. I highly doubt any of them are rated for more than 20 Amps. The 5V rail is probably an STPS2045CT or something similar. Sure there are 30 Amp rectifiers in TO-220 package, but they are less common and more pricey... and given that this is a very budget-looking PSU, I doubt we will be seeing such rectifier there. Also, the heatsinks (both primary and secondary) are quite thin and aren't really adequate to dissipate the heat generated by a 30 Amp rectifier running at full-tilt. Then again, neither is the rest of the PSU built well enough to benefit from larger heatsinks and rectifiers - the main transformer is size "33", so such old low-speed switching half-bridge topology like this generally becomes limited to 200 Watts continuous and *maybe* 250 Watts peak. Beyond that, it definitely jumps in the "will likely blow up" category.

On the positive side, at least the PSU appears to have adequate input filtering (both EMI/RFI and the rectified DC) on the primary. There's even a PPFC inductor! ... albeit a bit on the small side. But hey, it appears to not be fake either, which is a big plus already (yes, fake ones do exist in some of these really cheap PSUs.)

The one thing that I can't keep my eyes off of is this stupid stand-by booster circuit, seen here:
download/file.php?id=240955&mode=view
It's... pointless!
IIRC, I first saw it in a Jou-Jye PSU that someone posted on badcaps.net. O/P there was contemplating of what caps to use for it, since even the Japanese caps eventually failed in that circuit. After some back-and-forth analysis with him, we came to the conclusion that this circuit is, indeed, pointless - it wastes more energy than it helps to save by boosting the primary-side DC voltage. The conclusion is to just remove it completely. There will be no adverse effects.

AlexZ wrote on Yesterday, 07:20:

For comparison Chill CP-510A (510W), 3.3V+5V=330W max

Much better unit!
Only thing that worries me in that one is how long the "TL" primary cap will last. With APFC and it being rated only 400V *AND* being a rather low-quality brand... I just hope it goes out "gracefully", by loosing capacitance slow enough that the APFC circuit starts shutting down the PSU rather than MOSFETs going "kaboom".

Ydee wrote on Yesterday, 09:11:

What you will see (complete TEAPO caps, passive PFC, fan regulation, basic standard PSU back then) - line THN:

I have a very similar FSP, but just without the PPFC inductor. It was posted on BCN somewhere. I'll see if I can dig it (or probably should just dig my entire PSU collection there 😉 ).

shevalier wrote on Yesterday, 09:33:

Whats about this Chieftec?

Good stuff!
I believe that's a Sirtec -made unit from the High Power series.
From the two TO-247 rectifiers on the secondary heatsink, I can tell you that this PSU can (at least theoretically) do its full 5V rating current spec without fail. It's just a question of how well the 12V rail will stay in regulation with such a load, this being a group-regulated PSU. But it appears old enough to seem like it will be OK.
Definitely would be one of my GO-TO units for a very 5V-heavy PC if I had one.

shevalier wrote on Yesterday, 12:56:

Mates, we’ve already been bragging about our P..Pi..Pin.. PSU`s. :-) But no one has posted anything about this topic yet. For ex […]
Show full quote

Mates, we’ve already been bragging about our P..Pi..Pin.. PSU`s. 😀
But no one has posted anything about this topic yet.
For example, I use my retrorig for a year
- Pentium 3S (30 W) + Radeon 9800 (60 W)~90W
- Athlon XP (60 W) + Radeon 9600 (30 W)~90W
- an early Pentium 4 motherboard~90W

Actually, if you look in the 1st or 2nd post I made in this thread, I showed some sample calculations of how much the O/P's system would likely need... and hence why he/she wouldn't need anything too exotic in terms of a 5V-heavy -capable PSU. But I suppose these posts got ignored and/or buried by other discussions.

CharlieFoxtrot wrote on Yesterday, 17:10:

Does it say P CE-TUR or TUL? If so, the manufacturer is CEC International. It is Teapo/Capxon level stuff, that is they sometimes seem to last, sometimes not and are thus unreliable low quality junk. Very common brand with 2000s PSUs with Teapo, I always change both without thinking.

Yeah, unreliable is a good way to put it indeed.
I wouldn't say they were complete junk, though. Most lasted past the warranties, at least. I mean sure, that is still abysmal... but then there's way worse brands too.

CharlieFoxtrot wrote on Yesterday, 17:10:

At least many Seasonic PSUs are also often full of these. As quality brands wanted to save a buck, they opted these, Fuhjyy, Tayeh and bunch of other low quality trash and ruined their otherwise fine designs.

Interesting. I have not seen Seasonic with CEC caps before. But then again, all the old Seasonics I have run into were S12II platform in various Antecs (Truepower and Earthwatts).

CharlieFoxtrot wrote on Yesterday, 17:10:

Well, I guess most of the time is spent on writing overly long forum posts 🤣

If you were referring to me... don't you worry, I do spend a very good chuck of my time on checking and (if necessary) recapping my own PSUs, along with other electronics. 😉
The long posts are there, because I like reply to everyone that I think may be able to provide with relevant information, not because I like to type stuff just to argue or troll around.
Now, If my long and punctual posts annoy anyone, feel free to use ChatGPT or some other AI instead to get shorter "answers". 😁

Speaking of which... is there a character limit on Vogons? I know BCN had one and regularly ran over it before the old admin got tired of my complaints and increased it. 🤣
I suppose I shall find out soon if I keep going like this.
And FWIW, I only spend time typing here when it just gets too dark / to late to be on my bench to be doing recaps. Plus, it's a good way to unwind before going to bed at the end of the day, I think.

Mike_ wrote on Yesterday, 17:40:

I also opened a Fortron 350W PSU and this thing is definitely not fine. I guess I'll just throw it away, as it's a pretty generic PSU to begin with.

The attachment fortron_1.jpg is no longer available

The attachment fortron_2.jpg is no longer available

If it was mine, I'd recap and save this one, especially if it's an APFC-less unit (if anyone hasn't gotten the hint already, I have a strong distaste for APFC). It's probably not that bad of a unit. Bulged Fuhjyyus are just an ugly sight, but nothing that can't be remedied. Make sure to recap the 5VSB circuit completely, though, as I think this one is old enough to have the 2-transistor self-oscillating design. They go bad in these FSP PSUs when the "critical" small cap on the primary for that circuit fails. The result is destroyed 5VSB section.

But once recapped, should be fine for a retro 5V-heavy PC.
FWIW, I remove the "dummy" load resistors on these on the 5V rail, because they produce too much heat and cook the output caps unnecessarily.

Mike_ wrote on Yesterday, 17:40:

Half an hour to hour sounds very optimistic to me. 😁

Half an hour to an hour is indeed WAY too optimistic.
I think it would take this much time for a beginner just to identify all of the caps in terms of size. Brand and series? Probably even longer. And if they go looking for datasheets to actually try and do a proper recap by seeing what caps they have and what would be suitable replacements (or alternatively, posting the relevant info somewhere online to get help from others)... yeah, it's going to be a few days ordeal. And then, it wouldn't be until they do at least a few PSUs before they start to feel more comfortable with the whole process. All of this also assumes the beginner will have the proper equipment to do the recap and at least some experience in using it... which if they don't will probably take even more time.

So yeah, that 30-60 minutes for a beginner - no way, Jose !

That *may* be possible only if you already have all of the necessary capacitors in stock and ready to go in a unit that was disassembled already. Oh, and also if it's -not- one of those PSUs completely glazed with the organic tan/brown glue - that shit can take ages to remove sometimes (and removing it is necessary, both in order to replace the caps and in places where it might go conductive and cause further issues.) On that note, FSP PSUs (among a few others) can be pretty bad in this regard, especially earlier (closer to the 2000's) units.

Again, I'm not trying to discourage anyone from trying to do this type of work. But we really should try to be realistic here of what it takes to recap a PSU.

The time can vary by quite a bit. And not all PSUs are created equal, either. FWIW, some of the more packed stuff I have worked on easily spilled over an entire day's afternoon as a minimum. And if large heatsinks needed to be pulled to gain access to the caps or daughterboards removed... yeah, more like an entire weekend needed.

Finally... if you are slow with everything like I am 😁 , then triple/quadruple the required time easily.

Mike_ wrote on Yesterday, 17:40:

Also, while it's technically easier than recapping a motherboard, it's still AC equipment so I wouldn't recommend fixing it yourself to a beginner.

Nah, that part is fine... well, most of the time.
If the person doing it is the hasty kind that rushes through everything and regularly makes mistakes along the way... then yeah, probably best not to attempt this kind of repair - not so much because it would be dangerous, but because it will more than likely just end in disappointment / nothing working out.
Electronics repair requires punctuality, attention to details, and patience. If you don't have any of those, you probably won't get very far. And if you are reckless... then yeah, electricity can turn dangerous quite quickly.

appiah4 wrote on Yesterday, 20:31:

I tried running my 400w FSP with just a hard drive attached and it started making high pitched squealing sounds like a dying rat...

Is it because the load was too low maybe?

Maybe.
What's the full model number?
Are the caps still the original ones? And if yes, do they at least appear to be at least visually OK? (I know that doesn't tell the full picture, but it's better than nothing, usually.)
FWIW, some FSP PSUs don't deal too well at very low loads like that.

If you have some automotive / 12V incandescent or halogen light bulbs, you can use those as a load on the 12V and 5V rails. I usually use 2x oldschool 12V 20 Watt MR16 household lighting halogen bulbs: one on the 12V rail and one on the 5V rail. The one on the 12V rail will typically draw around 1.6 Amps, and the one on the 5V rail about 1 Amp - just good enough to satisfy many PSUs' minimum load requirements.

shevalier wrote on Yesterday, 19:42:

In the FSP on this platform, the supervisor is located on a small vertical board positioned perpendicular to the vertical board […]
Show full quote

In the FSP on this platform, the supervisor is located on a small vertical board positioned perpendicular to the vertical board housing the PWM controller.
Under the fan control board
If the board with the supervisor is present, it’s an excellent PSU.
If not (no voltage monitoring, only general short-circuit protection based on maximum power), then it’s just so-so.
A good source of spare parts.

There was no such board, or even footprint for it. Here's another photo I took of it.

momaka wrote on Yesterday, 22:21:

CharlieFoxtrot wrote on Yesterday, 17:10:

Does it say P CE-TUR or TUL? If so, the manufacturer is CEC International. It is Teapo/Capxon level stuff, that is they sometimes seem to last, sometimes not and are thus unreliable low quality junk. Very common brand with 2000s PSUs with Teapo, I always change both without thinking.

Yeah, unreliable is a good way to put it indeed.
I wouldn't say they were complete junk, though. Most lasted past the warranties, at least. I mean sure, that is still abysmal... but then there's way worse brands too.

Hmm, would you think it'd be worth the effort to recap that Enermax, even though output seems to be fine or just wait and see? I'd actually like to have that in working condition as it's a pretty nice PSU otherwise, so it would be a lot more likely to see actual use than the Fortron.

momaka wrote on Yesterday, 22:21:

If it was mine, I'd recap and save this one, especially if it's an APFC-less unit (if anyone hasn't gotten the hint already, I have a strong distaste for APFC). It's probably not that bad of a unit. Bulged Fuhjyyus are just an ugly sight, but nothing that can't be remedied. Make sure to recap the 5VSB circuit completely, though, as I think this one is old enough to have the 2-transistor self-oscillating design. They go bad in these FSP PSUs when the "critical" small cap on the primary for that circuit fails. The result is destroyed 5VSB section.

But once recapped, should be fine for a retro 5V-heavy PC.
FWIW, I remove the "dummy" load resistors on these on the 5V rail, because they produce too much heat and cook the output caps unnecessarily.

Ehh, it looks like there's lots of that yellow goo and even a couple of daughterboards with a bunch of small caps in them... If it's just a so-so PSU, I'd probably prefer not to spend the time for it.

momaka wrote on Yesterday, 22:21:

Maybe. What's the full model number? Are the caps still the original ones? And if yes, do they at least appear to be at least vi […]
Show full quote

appiah4 wrote on Yesterday, 20:31:

I tried running my 400w FSP with just a hard drive attached and it started making high pitched squealing sounds like a dying rat...

Is it because the load was too low maybe?

Maybe.
What's the full model number?
Are the caps still the original ones? And if yes, do they at least appear to be at least visually OK? (I know that doesn't tell the full picture, but it's better than nothing, usually.)
FWIW, some FSP PSUs don't deal too well at very low loads like that.

If you have some automotive / 12V incandescent or halogen light bulbs, you can use those as a load on the 12V and 5V rails. I usually use 2x oldschool 12V 20 Watt MR16 household lighting halogen bulbs: one on the 12V rail and one on the 5V rail. The one on the 12V rail will typically draw around 1.6 Amps, and the one on the 5V rail about 1 Amp - just good enough to satisfy many PSUs' minimum load requirements.

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to test and neither of them have this issue. I think this PSU is not happy about something internally, I will open it and check later; I am continuing the build with one of the healthy units for now.

The PSUs in question are model number ATX-400PNF. I have attached a recording of the sounds it makes. There is a small chance that it might be the fan (that will be the first thing I try, disconnect it and see if that works.. If so, a simple 120mm fan replacement is easy) but I think this sounds like the kind of noise the transformer would make, in which case it's probably a capacitor issue?..

I haven't gotten around to opening up and posting their interiors yet, maybe on the weekend. Some people are very dismissive of FSP units, but I find them to be fairly rugged and well built workhorses for the P3-AthlonXP era. I think every one of them are worth repairing and keeping, finding units with strong 5V rails is not easy anymore..

I'm really glad we have a PSU topic active, I really think it's a very overlooked part of the hobby, and I find it kind of fascinating, and want to learn more.

appiah4 wrote on Today, 07:55:

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to tes […]
Show full quote

momaka wrote on Yesterday, 22:21:

Maybe. What's the full model number? Are the caps still the original ones? And if yes, do they at least appear to be at least vi […]
Show full quote

appiah4 wrote on Yesterday, 20:31:

I tried running my 400w FSP with just a hard drive attached and it started making high pitched squealing sounds like a dying rat...

Is it because the load was too low maybe?

Maybe.
What's the full model number?
Are the caps still the original ones? And if yes, do they at least appear to be at least visually OK? (I know that doesn't tell the full picture, but it's better than nothing, usually.)
FWIW, some FSP PSUs don't deal too well at very low loads like that.

If you have some automotive / 12V incandescent or halogen light bulbs, you can use those as a load on the 12V and 5V rails. I usually use 2x oldschool 12V 20 Watt MR16 household lighting halogen bulbs: one on the 12V rail and one on the 5V rail. The one on the 12V rail will typically draw around 1.6 Amps, and the one on the 5V rail about 1 Amp - just good enough to satisfy many PSUs' minimum load requirements.

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to test and neither of them have this issue. I think this PSU is not happy about something internally, I will open it and check later; I am continuing the build with one of the healthy units for now.

The PSUs in question are model number ATX-400PNF. I have attached a recording of the sounds it makes. There is a small chance that it might be the fan (that will be the first thing I try, disconnect it and see if that works.. If so, a simple 120mm fan replacement is easy) but I think this sounds like the kind of noise the transformer would make, in which case it's probably a capacitor issue?..

I haven't gotten around to opening up and posting their interiors yet, maybe on the weekend. Some people are very dismissive of FSP units, but I find them to be fairly rugged and well built workhorses for the P3-AthlonXP era. I think every one of them are worth repairing and keeping, finding units with strong 5V rails is not easy anymore..

I'm really glad we have a PSU topic active, I really think it's a very overlooked part of the hobby, and I find it kind of fascinating, and want to learn more.

The noise is not coming from the FAN, it's harmonics/sound of the regulator feedback loop when, well, regulating. Normally you rarely hear it. However, it's not unusual this behavior increases when the output caps get bad, since the whole feedback look of the power supply is now basically miscalculated.

I honestly don't mind the FSP ones. They were often a "solid choice" for me in the past. Usually a re-cap and they served me very well.

tehsiggi wrote on Today, 08:23:

appiah4 wrote on Today, 07:55:

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to tes […]
Show full quote

momaka wrote on Yesterday, 22:21:

Maybe. What's the full model number? Are the caps still the original ones? And if yes, do they at least appear to be at least vi […]
Show full quote

Maybe.
What's the full model number?
Are the caps still the original ones? And if yes, do they at least appear to be at least visually OK? (I know that doesn't tell the full picture, but it's better than nothing, usually.)
FWIW, some FSP PSUs don't deal too well at very low loads like that.

If you have some automotive / 12V incandescent or halogen light bulbs, you can use those as a load on the 12V and 5V rails. I usually use 2x oldschool 12V 20 Watt MR16 household lighting halogen bulbs: one on the 12V rail and one on the 5V rail. The one on the 12V rail will typically draw around 1.6 Amps, and the one on the 5V rail about 1 Amp - just good enough to satisfy many PSUs' minimum load requirements.

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to test and neither of them have this issue. I think this PSU is not happy about something internally, I will open it and check later; I am continuing the build with one of the healthy units for now.

The PSUs in question are model number ATX-400PNF. I have attached a recording of the sounds it makes. There is a small chance that it might be the fan (that will be the first thing I try, disconnect it and see if that works.. If so, a simple 120mm fan replacement is easy) but I think this sounds like the kind of noise the transformer would make, in which case it's probably a capacitor issue?..

I haven't gotten around to opening up and posting their interiors yet, maybe on the weekend. Some people are very dismissive of FSP units, but I find them to be fairly rugged and well built workhorses for the P3-AthlonXP era. I think every one of them are worth repairing and keeping, finding units with strong 5V rails is not easy anymore..

I'm really glad we have a PSU topic active, I really think it's a very overlooked part of the hobby, and I find it kind of fascinating, and want to learn more.

The noise is not coming from the FAN, it's harmonics/sound of the regulator feedback loop when, well, regulating. Normally you rarely hear it. However, it's not unusual this behavior increases when the output caps get bad, since the whole feedback look of the power supply is now basically miscalculated.

I honestly don't mind the FSP ones. They were often a "solid choice" for me in the past. Usually a re-cap and they served me very well.

Ah, I see! So I should open it up and check the smaller caps on the +12V +5V +3.3V output rails, not the big huge caps on the input area? I'm guessing replacing these with caps rated for high ripple tolerance should theoretically fix the issue?

appiah4 wrote on Today, 08:37:

tehsiggi wrote on Today, 08:23:

appiah4 wrote on Today, 07:55:

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to tes […]
Show full quote

Thanks for the info. I thought it might be coil whine due to too little load, but fortunately I have 2 more of the units to test and neither of them have this issue. I think this PSU is not happy about something internally, I will open it and check later; I am continuing the build with one of the healthy units for now.

The PSUs in question are model number ATX-400PNF. I have attached a recording of the sounds it makes. There is a small chance that it might be the fan (that will be the first thing I try, disconnect it and see if that works.. If so, a simple 120mm fan replacement is easy) but I think this sounds like the kind of noise the transformer would make, in which case it's probably a capacitor issue?..

I haven't gotten around to opening up and posting their interiors yet, maybe on the weekend. Some people are very dismissive of FSP units, but I find them to be fairly rugged and well built workhorses for the P3-AthlonXP era. I think every one of them are worth repairing and keeping, finding units with strong 5V rails is not easy anymore..

I'm really glad we have a PSU topic active, I really think it's a very overlooked part of the hobby, and I find it kind of fascinating, and want to learn more.

The noise is not coming from the FAN, it's harmonics/sound of the regulator feedback loop when, well, regulating. Normally you rarely hear it. However, it's not unusual this behavior increases when the output caps get bad, since the whole feedback look of the power supply is now basically miscalculated.

I honestly don't mind the FSP ones. They were often a "solid choice" for me in the past. Usually a re-cap and they served me very well.

Ah, I see! So I should open it up and check the smaller caps on the +12V +5V +3.3V output rails, not the big huge caps on the input area? I'm guessing replacing these with caps rated for high ripple tolerance should theoretically fix the issue?

It's most likely the output, yes.
My go it often: If I'm re-capping anyways, I go all in. Take quality low-ESR caps with at least the same capacitance and voltage rating. Higher voltage rating will cause any harm, it'll usually have lower ESR than the lower voltage caps of the same series. Don't need to over-think it. Just slam the same capacitance, voltage + low ESR in there as has been in before and you should be good.

tehsiggi wrote on Today, 09:33:

appiah4 wrote on Today, 08:37:

tehsiggi wrote on Today, 08:23:

The noise is not coming from the FAN, it's harmonics/sound of the regulator feedback loop when, well, regulating. Normally you rarely hear it. However, it's not unusual this behavior increases when the output caps get bad, since the whole feedback look of the power supply is now basically miscalculated.

I honestly don't mind the FSP ones. They were often a "solid choice" for me in the past. Usually a re-cap and they served me very well.

Ah, I see! So I should open it up and check the smaller caps on the +12V +5V +3.3V output rails, not the big huge caps on the input area? I'm guessing replacing these with caps rated for high ripple tolerance should theoretically fix the issue?

It's most likely the output, yes.
My go it often: If I'm re-capping anyways, I go all in. Take quality low-ESR caps with at least the same capacitance and voltage rating. Higher voltage rating will cause any harm, it'll usually have lower ESR than the lower voltage caps of the same series. Don't need to over-think it. Just slam the same capacitance, voltage + low ESR in there as has been in before and you should be good.

Thanks. Checking on badcaps.net reveals others have had the same noise issue and it was resolved by replacing the Teapo 1000uf 6.3V capacitors on the output (most of which were bulging). I think it is a good idea to recap these on even the units that seem to work fine preemptively. I have quite a few decent 1000uf 10V Low ESR caps to do this with. This will be a fun project for the weekend..