Dell TFX power supply - made by Delta DPS-250AB-28

[kleung]

Well, I can't complain as this power supply has been in my Dell vostro 200 slim computer at the office for 7 years. When the PSU died; it did not seem to take out anything else either which is a bonus.

The power supply model is:

Delta electronics - DPS-250AB-28 B

These slim form factor pc's from dell were marketed as the Dell 200s or the Inspiron 530s here in canada.

Surprisingly, the PSU's are a TFX form factor manufactured from delta. The soldering inside was very good. Not sloppy.

One morning, the PC just would not turn on. Looking at the motherboard, it was still receiving power (amber light was dimmer though) so I think it might have been a standby circuit capacitor that died.

Opened up this 7 year old psu (that sat inside a cupboard with a small windo) and the ONLY capacitor that was bulged was a 16v-1500 uF capacitor from.... CapXon.

I replaced it with an old nichicon cap I had lying around and the unit powers up. I'm not sure how reliable it will be now and if any of the gurus can tell me if this is just a standby cap; that would be great.

I have enclosed pictures. I apologize for the blurriness.

There aren't many forum discussions regarding TFX power supplies so I'm adding to the knowledge base.


BTW - I tested the badcap and it was COMPLETELY bad. 0 capacitance.

[c_hegge]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

That cap was filtering the 5vsb output. Depending on what series the Nichicon cap you replaced it with was, it may actually be more reliable now.

[kleung]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

Thanks for the quick comment/reply.

I went into the office today to inspect my other 3 dell vostro 200s (purchased exactly the same time).

To add to the knowledge base.

I discovered a quick way to check for the bad cap without disassembly.

These 3 systems ALL booted up easily. HOWEVER, when I disconnected the power cable and drained the capacitor (by pressing the power button with the PSU unplugged a few times); the psu's with the bad caps would not power back on right away when plugged back into the wall.

They DID eventually power up after a few minutes left plugged in though.


Can't edit the original post but the capacitor that failed was a CapXon 16v- 1500 uF GL series capacitor if that matters to anyone


This revealed (along with visual inspection to corroborate) that 2 out of 3 systems had failed/failing power supplies.

LUCKILY, the design seems to be in a way that it didn't take out any additional components and only manifested itself as a refusal to power on right away.

Since it is such an easy 1 item recap; I will be recapping the psu's as well as ordering a new tfx PSU as backup.

[kleung]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

That cap was filtering the 5vsb output. Depending on what series the Nichicon cap you replaced it with was, it may actually be more reliable now.

Also, just read with great interest your review of the InWin/power tfx PSU. It's pretty cheap here to pick up that unit in Canada.

Any further follow-up comments on that psu?

http://www.hardwareinsights.com/wp/i...-tfx-review/4/

[Behemot]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

Regarding TFX, Seasonic is working on a new 80 PLUS Gold 250W (!!!) unit. I will have sample when it is ready. There is increasing competition in TFX and SFX market, some of the high-end units tread that In Win into dust.

[c_hegge]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

^
There's also an 80plus gold In Win 300W TFX unit available here too now. I haven't reviewed it, but I can tell you that the main differences are that it uses Teapo caps (which might be a little better than Samxon GF), has an extra SATA, but one less molex connector and, being more efficient, it is quieter.

With that said, though, the older non-80plus In Win PSU which I reviewed there would probably be just fine to fix up an older PC like one of these (or to have as a spare which you can quickly swap in if one of the other PSUs fails). If you can get it at a good price, I would say go for it.

Another thing to bear in mind is that Dell use PSUs from about four different manufacturers (Delta, Hipro/Chicony, AcBel Polytech, and Huntkey) interchangeably on their PCs.

[Behemot]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

Seasonic has 80 PLUS Gold 300W unti for VERY long time. Now there will be 250W one. The 300W one has only japanese caps, the 250W will most likely have them too.

While I agree any TFX unit would be good for such computer, high-efficiency one will pay itself on electricity savings after some time and it will also run more silent.

[c_hegge]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

^
It will be quieter, but at a low wattage like this, the savings in electricity will be almost meaningless, especially in the US/Canada, where power is dirt cheap compared to here or Europe.

[kleung]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

Thank you for the discussion. You are absolutely right about the different suppliers.

I have 5 vostro 200s units for the office; 4 used delta (which had the bulging caps) and one used a bestec tfx unit.

I ended up replacing the badcap on 3 of the delta units; and then swapping the last one out with a seasonic 300w gold just to see how it will compare/last with my repaired PSU's.

The seasonic had some initial coil/component whine when it was plugged in but that seemed to have gone away after 15 min. or so.

Since the system sits inside a poorly ventilated cupboard; we will see much longer they last.

@ 7 years longevity; I have no reason to complain.

Thanks for providing feedback guys. Always good to have the professionals weigh in.

[CaliforniaMartin]

Re: Dell TFX power supply - made by Delta DPS-250AB-28

kleung, thanks for posting this cap solution. I happened upon an INOP Dell Inspiron 530s due to the power supply. After replacing the bulging cap, all I had was a 2200 uF, all is working fine now. Thanks again.