Ultra Xfinity 600w 5vsb mod

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

there were no obvious signs of heat damage... not that i could see anyway. it is a black pcb, but all the silkscreening was pearly white.

will check when I get a chance

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

If the PSU has had a few years of use, then my general rule of thumb is that if they are discolouring the PCB, then replace them, otherwise, they are fine.

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod





she's dead.

recapped it, was a very tight fit,

still makes the dreaded acing like noise it made before. 5vsb is in spec.

gave it the power on signal (green to gnd), no change. 0v on everythign but 5vsb.



now to find a 400W+ psu for the project box this was for... (my biggest is a 300W delta)

[momaka]

Re: Ultra Xfinity 600w 5vsb mod

Wait, wasn't this PSU working before??

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

Wait, wasn't this PSU working before??

minus some bad screeching, yes

i know that the guts were squished a bit after the recap... the new caps were physically larger than the stock caps.



i don't know what to say here...

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

any ideas on what could have killed it?

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

Either it doesn't agree with one of the capacitors, you shorted two traces, or you have a cold joint. I had this when I was re-building the rexpower and it took me a few days to spot the solder bridge, as it was only very small.

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

Either it doesn't agree with one of the capacitors, you shorted two traces, or you have a cold joint. I had this when I was re-building the rexpower and it took me a few days to spot the solder bridge, as it was only very small.

noted- I'll check.

only values chaned is the 2 5vsb caps are 10v 1000uf, as opposed to the stock 16v 680uf.

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

Either it doesn't agree with one of the capacitors, you shorted two traces, or you have a cold joint. I had this when I was re-building the rexpower and it took me a few days to spot the solder bridge, as it was only very small.

DING DING DING!

found some solder bridges on the primary side. fixed, and aside from the screeching (me thinks its a no load issue?), it works.



then again, i was rushing thgere, as the superglue used on the loose traces was vaporizing from the heat, and i did't want to pass out or the like. that, and it made my nose burn.

chegge,

I owe you...

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

Cool. Now you owe me the power supply. After all I did help you fix it Just kidding

Try it with some load. I had the same issue with those Widetech/Great Wall power supplies. They had a slight squeal with no load, but they were fine as long as I loaded the 5vsb and 12V rails, it was fine.

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

Cool. Now you owe me the power supply. After all I did help you fix it Just kidding

Try it with some load. I had the same issue with those Widetech/Great Wall power supplies. They had a slight squeal with no load, but they were fine as long as I loaded the 5vsb and 12V rails, it was fine.

all i have for load is a dead sata hdd... and the 4 fans in the case. currently i have all of those running, no noticeale ripple on the analog meter. the voltages are also in spec.

oddly, the fans have yet to turn on... everell, the original owner, noted that the fans never turned on for him either... the stock fans were wasted, and i replaced them... either the thing hasn't gotten hot enough or the fan controller has issues.

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

Keep an eye on them once you have some more load. Those heat sinks are fairly chunky, so it wouldn't surprise me at all if the fans don't spin when the power supply is cold. If you do think it has problems, though, it looks like an add-on daughterboard, so scavenging one from another PSU slould be easy.

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

Keep an eye on them once you have some more load. Those heat sinks are fairly chunky, so it wouldn't surprise me at all if the fans don't spin when the power supply is cold. If you do think it has problems, though, it looks like an add-on daughterboard, so scavenging one from another PSU slould be easy.

i do have a partial spare from a junked 550w ultra... but it is missing most of the circuit (much more basic)

once I get the board for the project in and i get it recapped, then I can put some REAL load on it...

ps- I still feel like a .

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

Don't worry. It took me ages to find the short on the rexpower.

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

Cool. Now you owe me the power supply. After all I did help you fix it Just kidding

Try it with some load. I had the same issue with those Widetech/Great Wall power supplies. They had a slight squeal with no load, but they were fine as long as I loaded the 5vsb and 12V rails, it was fine.

i loaded the 5vsb with an old abit BH6 i had... the noise persists.

i unglued some things (yucky yellow glue)... i wonder if something is rattling?

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

Did you replace -all- of the capacitors, including every tiny one? If not, then it could be that one of them is the culprit (assumming that the squeal was there before the recap). I used to have this issue with the Antec StupidPowers, where they would squeal even after replacing all of the major caps, but a complete recap (minus the primaries) seemed to fix it.

You should probably find out where it's coming from as well (use the old straw to the ear trick). It will be one of the coils, or the feedback transformer (probably the middle one).

[brethin]

Re: Ultra Xfinity 600w 5vsb mod

Try loading the 5v rail heavy to test (at least 15 amps) and see if the noise goes away, my guess is it will.

[momaka]

Re: Ultra Xfinity 600w 5vsb mod

i loaded the 5vsb with an old abit BH6 i had... the noise persists.

Some PSUs just like to whine. Both the 200W Astec and the 185W Lite-ON in my computers produce a fairly loud squeal. Both of these PSUs have been running for close to 10 years now without problem, so I just disregard the noise.
In any case, if you're worried about your motherboard being killed by the 5vsb, just install a 5.1v to 5.5v zener diode across the 5vsb. If something goes wrong with the 5vsb and the voltage on 5vsb goes over the zener diode's voltage, the zener diode will short out and kill the 5vsb. Not a very neat solution, but at least your motherboard won't die.

[c_hegge]

Re: Ultra Xfinity 600w 5vsb mod

Disregard the noise? Impossible! It's REALLY, REALLY, REALLY annoying!

[ratdude747]

Re: Ultra Xfinity 600w 5vsb mod

it is more like an arcing noise than a squeal come to think of it. almost like a hiss.