Atx power supply...definitive solution

[superdavies]

Hi

I Red many topics regarding the use of ATX power supply for using with midibox but I think that maybe there's the needing of make something clear!

I'm not sure about the things I understand, but I think that +5v out of a standard PC PSU is good for some projects (midio, midibox64 ecc) and not good for others (sid ) that's because ATX is switched and this carry noise in the audio line. Is it right? Maybe is a good things to explain the problem in a definitive way because I think many midiboxer would like to use this kind of PSU. What's the pros of using it? what's the reason for not suggesting its usage? if is it possible to use, how many cores it can supply? For what project it's good?

Thank to anyone who want to contribute!

Andrea

[stryd_one]

I think that +5v out of a standard PC PSU is good for some projects (midio, midibox64 ecc) and not good for others (sid ) that's because ATX is switched and this carry noise in the audio line. Is it right?

Yep!

What's the pros of using it?

It supplies power ;D

what's the reason for not suggesting its usage?

Audio. If it's all MIDI, you should be right.

if is it possible to use, how many cores it can supply?

That depends on the capabilities of the PSU and the power requirements of the midibox

For what project it's good?

Anything without audio... although I suspect that the AINs would be effected too (I've never used an AIN)

There's stacks of interesting info if you search for 'switching psu' (without the quotes)

[DrBunsen]

I would imagine, as these supplies are commonly rated for a couple of hundred watts, they should supply all the cores you can throw at them pretty happily :)  If in doubt, add up your cores (as well as LCDs, LEDs etc) and check the individual current ratings for the 5V, 12V etc marked on the PSU.  One watt per core is more than generous at my GUESS.

You can probably get away with a small one from a FlexATX or server case rated around 100W with no problems.