TELVM wrote:

^ My guess from a distance is that the caps circled in red are probably related to +5VSB circuit, at least two of them.

I'd replace with lowish ESR, same uF, and 50V rated (regardless of the originals being 25V or 35V) from some quality long-life series, like Chemicon KYA, Panny FR or Rubycon YXJ.

Thanks 😀

When the PSU in the Dell dual Socket 603 i860 system let out the magic smoke I went on a hunt for a backup system to use for the intended purpose until I have repaired the broken Dell PSU. I ended up with a 30 euro year 2002 vintage Compaq/HP system. The Prestonia CPUs the system came equipped with are nice for sure... and a Quadro4 380 XGL video card is totally suitable when it comes to showing the desktop but perhaps not for the things I had planned...

Upgrades were needed! This brings us to the subject of this thread, the PSU.

Compaq rated this PSU at 180W for the 12V rail responsible for providing power to both CPUs and 132W for the 12V rail that is called I/O. The I/O 12V rail powers the non CPU related DC/DC converters on the motherboard and also all other stuff like HDDs and such. If we go by specs I kind of need the CPU rail to handle 22% more than it's ratiing and the I/O rail to handle a fair bit more aswell.

I have already tested the system with the upgrades and it's fully stable. Even if the real power consumtion numbers are a bit less that the max speciafied for the CPUs and video card I have a feeling that Compaq really rated this PSU with a huge safety margin as it's exhaust air isn't the least hot even when the system is stressed during heavy benchmarking.

Anyhow here are some pictures. The pictures don't show that much of the inside as it's filled to the brim with stuff, a huge contrast from the cheap gutless wonders of the era.

The Compaq WTX460-3505 sticker.

The inside 1.

The inside 2.

The inside 3.

Does anyone have any experience with this unit? How much abuse can it take? 😈 😀

Tetrium wrote:

Are there NOS or are these genuinely newly made products? Interesting! They seem sold out here in The Netherlands though. […]
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Richo wrote:

zakurowrath wrote:

Has anyone ever used the StarTech PS2POWER230 230W AT power supply? I've bought a lot of products from StarTech over the years and never had a problem with them and after reading this thread, I'm kind of wondering should I really go for their newer AT power supply or could I go with a semi modular ATX power supply like the PC Power & Cooling Silencer Series 400 Watt (PPCMK3S400)?

FSP still sells new AT PSU: fsp fortron spi-250g
They cosy around 50 in the netherlands new. I usually just scavenge old AT computers for the AT PSU and inspect/clean them.

Are there NOS or are these genuinely newly made products?
Interesting! They seem sold out here in The Netherlands though.

I did some more looking around and apparently there is also at least one FSP PSU still being sold with good amps on 5v, or at least according to tweakers.net
It's the FSP FSP400-70MP, link to FSP website itself. The specs can be seen by clicking on the right-most pic, but I found the rails were really low and when I saw it listed 300W max on 3.3v, 5v and 12v, I found that to be utmost peculiar...till I noticed they put the specs of the 300W model in there 🤣!

It's very expensive though for a 400W unit, but 30A on 5v is pretty much enough for any sA (maybe except for sA dual CPU).

Srry for late reply
Believe those ate new judging it's price, didn't bother with it since I have plenty AT psu now with good caps.
My socket A draws 30A from the 5V at max load so I needed one with 35A at least and those are rare. Modern psu just don't offer those kinds of amps on the 5V unless you buy a PSU of at least 800W.... (My corsair 750 had 33 or 34A on 5V)
My hiper does the job wonderfully after I recapped it. Still it's hard to find a good PSU with high A on 5V these days, I started looking out for some parts for a dual tualatin build and my calculations came at a similar PSU as my Socket A. Psu calcs don't offer p3 options so I have no idea how much watts I need for a dual tualatin build with likey a Geforce 3/4 TI depending on what I can get

Richo wrote:

so I needed one with 35A at least and those are rare.

I have a thread for that 😀. Let us know what your experience is! The thread also has some other options if you need another high powered ATXv1.3 PSU.
The PSU Matchup Thread

Got an AOpen PSU today with a nice 5v rail

Besides dust and a single bulged cap, I found this:

Should I find this concerning?

Yes. That resistor has been getting way hotter than it should. Also, I like the can filter on the AC receptacle.

https://www.youtube.com/watch?v=efK7mw8eYiE

Thought this wold be better in this thread.
Currently toying around with my antec true 330 which i posted here some time ago, however it is having issues in speed fan.
Speed fan does measure the psu voltages available usually, however my antec it's -12V and -5V are either non functional or there is something seriously wrong with them. The voltages are fluctuating heavily well beyond its allowed specs the -12V goes to -6V as an example. It's currently being used on my gigabyte GA -60XT with the Intel 815EP. Does anyone have an idea what the cause could be? Regular voltages are dead stable rarely fluctuating beyond 2-3%
Normally I wouldn't pay attention to this since I don't really use the voltages, but it's nibbling in the back of my mind.

To me, some of the Speedfan ratings are not to be taken seriously.
For instance, +12V on the rig that I'm writing this reply right now, it's reading 9.59V.
So if its really out of range..I think you can ignore it. I've had this with multiple rigs, of all kinds of different manufacture and different generations.

Here is something for fun. I recently upgraded my main system's PSU from a Sirtech HighPower 500W ECO (a Turkish market exclusive low cost model) to an FSP Hydro 600W 80+ Bronze. While I was at it I also took the old unit apart and took photos of it, for all of our learning. Enjoy, and let me know how crappy it is. It served me well for over 6 years. Adding a sound card was the straw that broke the camel's back.

http://image.bolterandchainsword.com/uploads/ … 1505_317147.jpg

http://image.bolterandchainsword.com/uploads/ … 1505_493853.jpg

http://image.bolterandchainsword.com/uploads/ … 1505_424251.jpg

http://image.bolterandchainsword.com/uploads/ … 1505_463349.jpg

http://image.bolterandchainsword.com/uploads/ … 11505_48947.jpg

http://image.bolterandchainsword.com/uploads/ … 1505_137842.jpg

http://image.bolterandchainsword.com/uploads/ … 11505_95843.jpg

I've seen better, but I've seen a lot (!!!) worse. I can't see the semiconductors to know for sure, but they might have used a Chemi Con capacitor with the two transistor standby circuit. Ideally, they'd use a regulator that protected against overvoltage, but at least a decent cap will keep your motherboard from being Bestec'ed.

Had the joy (!) of cleaning a 25 year old AT PSU today. Apparently its fuse blew up at some point in its lifetime as there are some very stubborn scorch marks inside of the case next to where the fuse is soldered. It works for the moment though. Here is what it looks like on the inside, for laughs. Click for larger photos.

Love that deathtrap of a transient input filter.

gdjacobs wrote:

I've seen better, but I've seen a lot (!!!) worse. I can't see the semiconductors to know for sure, but they might have used a Chemi Con capacitor with the two transistor standby circuit. Ideally, they'd use a regulator that protected against overvoltage, but at least a decent cap will keep your motherboard from being Bestec'ed.

+1. Seems to be a pretty decent PSU. A bit low power, I would not load it over 300W.

gdjacobs wrote:

Love that deathtrap of a transient input filter.

Well, were AT PSUs of the time (ie. 25 years ago) generally any better? I mean, would more money get you better quality PSUs all the way back when? I remember just buying cases and going with whatever came in them; even Pentium II systems did not have power draws worth mentioning..

Much like the early Pentium II/III era and today, yes - AT power supplies could be a lot better. From what I have experienced (and this isn't a large volume of AT power supplies), most AT power supplies were built better than the early ATX power supplies. This is just an assumption based on what i have seen and isn't meant to be a general indicator. I imagine where one was living in the world at the time would also make a difference in terms of quality of PSUs they would obtain from stores and distributors <shrug>.

But here is a photo of the primary side filtering from an AT power supply I recapped earlier this year. Much more acceptable.

The filter on my Delta test AT supply, date code 21st week of 1993.

Proper safety rated X and Y caps. More coils than X caps, so a different filter topology than CkRtech's example.

Snowdrop contemplating having a nibble.

Would any of you fine gents please drop by on my Compaq Deskpro troubleshooting thread and let me know if the PSU is the source of my troubles over there? I have shots of its innards in the last post.

Champion Level Suckage?

Look at those heat sinks and transformers. About as beefy as a bowl of Ramen.

You only need an input filter if you want radios to work.

High quality capacitors for long life! Fuhjjyu too!

I guess they at least tried.

Blob is best, plus that solder flux is a definite mark of quality. Notice the lovely hot spot in the middle of the board?

That PSU is quite ok compared to these :

One has a thin sheet as heatsink 🤣