wave wrote:

GPS-400AA

That's a Delta 😀 😀 😀 😀 😀 😎 😎 😎 😁

Delta is in the top 5 of best power supply manufacturers. Definitely worth recapping and keeping!

Nice, I think I will replace the AOpen 300W unit with this one and put the AOpen PSU without the bulging blue cap in the spare P3 1400-S system. I have loads of stuff I should recap but I do not do much recappng although I do have a good soldering station and I have done it before. Just getting the caps at a decent price is a pain here in Sweden.

Hmm, I see. Well, a trick to get away with junk caps (provided they are not already bad) is fan modding the psu fan controller so that it doesn't overheat. The psu remains fairly silent, but the fan spins a bit faster and the caps are not cooked.

wave, what the other four would be? Are Astec, Seasonic and FSP on the list? 😀

After some more testing I came to the conclusion that that the AOpen 350W unit with the bulged blue cap has the best voltage regulation out of these three units... The 300W AOpen and the Chieftec (Delta) aren't exactly bad but the 5V rail drops to ~4.9V and the 12V rail to ~11.85V during heavy load with both those units. The 350W AOpen units 12V rail idles at ~12.15V and drops to ~12.00V during heavy load while the 5V rail barely moves at all. The difference is enough to make 1600+ MHz work with the CUSL2-C and the Tualatin or not, at least with the Geforce 6800GT in the system.

To conclude: The PSU is in another cast... junk pile.

Not easy to tell...

Seasonic is my number 1.

Hipro and Lite On are very good too! Enhance is almost flawless! I like FSP but some of its designs had some issues (for example high ripple).

Herolchi is 1 of my favorites, but it is not on top 5.

And there are many OEMs that I just don't remember right now.

Today I would say Flextronics is also a contender for the best PSU OEM title.

Im having an eventful morning 😁. I was going to test some other PSUs with the spare Tualatin system to see if I could find another PSU that would let me overclock as high as the AOpen 350W unit. I tested a Cooltek 500W PSU with two bad caps just to see how it performs, its perhaps also a unit worth recapping. I know the Cooltek unit performed OK even with the two bad caps as I have pulled close to the maximum load from it only weeks ago (before I found the two bad caps and replaced it).

When I powered on the system with the Cooltek unit something exploded after a few seconds. It was a very load bang/pop, the sound of for exaple a solid cap exploding but the system diddnt power off and kept booting Windows until I reached the power switch on the PSU. Well its a spare system no harm done I thought and started investigating. The PSU is still good, or as good as it was from what I can tell as the first thing I did was to test it with a junk P4 motherboard. Then I connected a Fractal Design Newton R2 PSU to the Tualatin system and powered on, everything still works...

Im glad I kept investigating though as I found the issue an hour later, it wasnt related to bad caps in the PSU... When you buy a used system its always good to disassemble the whole system and assemble it again just in case the previous owner has done a poor job. When you fail to do this stuff like this can happen.

This screw is identical to the 6 screws holding the board to the motherboard tray, it has probably been lodged between the motherboard and the motherboard tray since the system was first built...

The system did run with the loose screw in that position but I guess it moved, created a short and something blew because of it. Im thinking it was some sort of small resistor as I have not found it yet. It cant be a very important resistor (or whatever) as I managed to run both 3dmark and HCI memory test without issues before I found the culprit.

Now I will disassemble the system and rebuild it before I do anything else...

Here are two pictures of the Cooltek 500W unit with bad caps. Is this unit worth saving for recapping?

^ Looks decent from a distance. Fuhjyyus aside, one can see generously sized PI coils and even shunt resistors (meaning the two +12V rails are probably real) in this 2005 review.

TELVM wrote:

^ Looks decent from a distance. Fuhjyyus aside, one can see generously sized PI coils and even shunt resistors (meaning the two +12V rails are probably real) in this 2005 review.

Nice, the 45A 5V rail should make it a good match for some crazy Socket-A system 😀

In the end I decided to keep the 300W AOpen unit in the Tualatin Windows 9x system and the 350W AOpen unit with the bulged blue cap in the spare Tualatin system. I could not find a better spare unit in my PSU pile with a 120mm fan that wasnt too weak, had (more) bad caps or was over the top overkill. I do have more spare PSUs somewhere, among them a nice Seasonic SS-500HT unit but they are probably mounted in half built systems or collecting dust in some box covered with other boxes.

RacoonRider wrote:

TELVM, since you're obviously quite experienced in PSUs, do you think a Powerman 450W rated PSU can be the reason for 3 PCI-E videocards failing one after another in the same PC? I'm starting to think I need a replacement.

Might want to check what power you need for the card you are running. Not saying you haven't but its better to double check. I made the mistake of running my HD 3850 AGP 8x on a 350W PSU, its a hog needing 400 or 420. Just a bit of advice.

TELVM, i see alot of pics coming your way in the future. Great info !!!

finally, the Heroichi PSU is done:

fan is replaced also with a high-quality Noctua running through it's Low-Noise-Adapter , it provides a nice silent flow. Strangely (to me atleast) it appears that the GND signal to the fan wasn't exactly GND... it appears to go through a transistor , maybe a way to speed-control it? I bypassed it to get the Noctua fan working.

So I decided I recap another AT PSU (posted some pics earlier in the thread here: Re: A tale of two PSUs) since I am thinking of doing a 386DX build again.

Changing the caps was a simple matter as they were not that many and the input ones were Rubycons so I left them as-is:

I also added that filtering pcb at the input , sodler looks kinda ugly but it's solid 🤣 🤣 🤣

I don't understand half of what is going on in this thread, but I love seeing the work being done. I hope to find the time to attempt to re-cap my Antec HE-550 one day, and I will most definitely come to this thread for help. Just out of curiosity, has anyone actually recapped one these power supplies? Based on review photos, it looks like the primary capacitors are generally decent, it's the secondary ones that are questionable.

I have one of those infamous Antec tru-power 380 watts full of F-u caps on hand and it is the reason why my favorite p4 board in the world is dead!!! (besides its own icky dead caps of course 🤣) kinda thinking of recapping that.

They're based on a CWT-built unit, according to this site. Despite my distrust and dislike of CWT, it's still worth it, since it can supply 35A on the 5V-line. You might need to replace the primaries on them too, which will cost a fortune. I see that you can pay up to $30 for some of those big capacitors.

Evert wrote:

They're based on a CWT-built unit, according to this site. Despite my distrust and dislike of CWT, it's still worth it, since it can supply 35A on the 5V-line. You might need to replace the primaries on them too, which will cost a fortune. I see that you can pay up to $30 for some of those big capacitors.

Ouch forget that then. I may keep it hand as a novelty then. If it wasnt for that psu my Soyo p4s Dragon which I recapped would probably still be functional. But over a decade powered by that PSU damaged it beyond repair I think 😢

Ooh! That sucks, the Soyo Dragon boards have a lot of character and charm and were quite interesting to look at too.

I havent thrown it out yet just because my dad bought it new and it was THE computer in my child mind from 2001 to 2010 😁 maybe one day il get a replacement that works and hang this one on the wall as a replacement. My AsRock 990fx board has a similar PCB color and I love it! Now if only it had the purple pci slots eh?

Another illustrative article at Uncle Tom's:

Tom's Hardware: Antec Aria AR300 PSU Repair

http://media.bestofmicro.com/4/2/517250/original/02.03.01-5VSB-Orig.png ^ "... Surprise! I thought the SL300 was bad with power- […]
Show full quote

^ "... Surprise! I thought the SL300 was bad with power-up transients up to 16V, but the AR300 beats it hands-down with steady state transients up to 27V 😵 😵 😵 . I am surprised my P4's motherboard survived ..."

"... those two-transistor 5VSB designs are potentially dangerous. When coupled with low-endurance capacitors, they are downright evil as shown in both my SL300 and AR300 repairs ..."

"... Just like the SL300, the AR300 demonstrated how efficient flyback supplies are at killing their output capacitors evenly, albeit with some extreme heat assist in the AR300's case ..."

"... In retrospect, I am a little surprised this power supply managed to give me at least four solid years while powering my 3GHz P4C and Radeon X700 in such an airflow-challenged enclosure through thousands of hours of moderate to heavy use (for a 300W PSU) and nearly 24/7 power-on time. With that said, I am not pleased with how close this unit may have come to ruining one of my PCs through what I like to call engineered failure--using some of the cheapest parts possible in near-critical locations to barely exceed warranty requirements, effectively guaranteeing high failure rates shortly thereafter ..."

· Heat murders electronic components in general, and crappy electrolytic capacitors in particular.

· Good case ventilation is a must, to prevent heat from killing our PCs.

· When the PSU's +5VSB caps bite the dust, +5VSB rail voltage and ripple skyrocket and the mobo is placed on the death row.

keropi wrote:

So I decided I recap another AT PSU (posted some pics earlier in the thread here: Re: A tale of two PSUs) since I am thinking of doing a 386DX build again.

Changing the caps was a simple matter as they were not that many and the input ones were Rubycons so I left them as-is:

I also added that filtering pcb at the input , sodler looks kinda ugly but it's solid 🤣 🤣 🤣

Forgive me for being daft, but I have scanned this forum thread and I am curious about what filtering PCB you are talking about here.

^ last photo of this post: Re: A tale of two PSUs , right behind the power input , this was not part of the original psu.

Interestingly I abandoned this PSU , the +12v line only outputted ~11.2v ... don't know why.