picopsu-80, what have you managed to run off of it?

PSUs: The source of DC power for all components in the PC & often a big noise source.

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porkchop
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picopsu-80, what have you managed to run off of it?

Post by porkchop » Wed Oct 17, 2012 7:33 pm

it's recently come to my attention that it only specs 12v at 4A, which makes me think it won't be enough for a barebones 65w trinity based pc.
having said that i am currently using it to run a admittedly heavily undervolted and underclocked athlon ii x3 440 @2.1ghz max and -0.275v undervolt, which according to my kill-a-watt clone maxes out @68w at the wall, so perhaps there's hope for me yet.

any thoughts or experience?

btw not limiting the cpu to 2.1ghz crashes it, i'm pretty sure at this point i'm hitting the limit of the picopsu-80 as my delta brick is rated for 84w.

Vicotnik
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Re: picopsu-80, what have you managed to run off of it?

Post by Vicotnik » Wed Oct 17, 2012 11:42 pm

Since the picoPSU doesn't really do anything with the +12v other than to pass it through it's possible to bypass the picoPSU and feed stuff that needs 12v directly from the brick. I usually wire my picoPSU systems so that the 4pin +12v connector that feeds the CPU gets power directly from the brick.

With the picoPSU in it's vanilla configuration I've had problems with the +12v rail dropping under load on relatively high power systems. If you're experiencing instability, check the +12v from a molex using a multimeter. The acceptable range according to the ATX standard is ±5% (+11.40v to +12.60v). If you see levels close or below the lower limit, stability could improve with a bit of rewiring.

porkchop
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Re: picopsu-80, what have you managed to run off of it?

Post by porkchop » Thu Oct 18, 2012 3:04 pm

the 12v line definitely droops but is always within spec, the lowest it went was ~11.60v during a stress test.

as for rewiring i think i'm too electrically nooby and lazy to even try :)

i was really after some feedback regarding a vanilla picopsu-80, some more hope that everything will be fine when i upgrade my pc. time will tell though, i've got back up psus too so it's not like it has to absolutely work.

btw those builds in you sig look really nice!

edh
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Re: picopsu-80, what have you managed to run off of it?

Post by edh » Fri Oct 19, 2012 12:06 am

porkchop wrote:the 12v line definitely droops but is always within spec, the lowest it went was ~11.60v during a stress test.
How was this measured? It could still be that there is excessive ripple that you wouldn't see on the DC measurement. If you have a true RMS multimeter you could also make an AC measurement of the ripple to see if this is within spec.

porkchop
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Location: Australia

Re: picopsu-80, what have you managed to run off of it?

Post by porkchop » Fri Oct 19, 2012 2:09 am

measurements are what the motherboard spits out, i have no equipment that could measure it otherwise.

i'm not fussed at all about stability, its fine when restricted to 2.1ghz.

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