12V Ripple

As long as the ripple does not cause the 12v to drop below the atx spec.

Then don't worry.

That psu is fine.
 
You people trying to assure me that in UK they don't teach even basics of electricity in school?

Ripple is AC waveforms (of line frequency and higher) "riding" on top of DC and while it doesn't change DC voltage value that high freq jumping makes it harder for voltage requlation circuits of pretty much every PC component to provide stable voltage to critical components.

And it's measured with oscilloscope, not with any multimeter. That was just measurement of voltage regulation/stability. (with group regulation in action with lightly loaded 5V going slightly up)

For ripple limits are 50mV peak to peak for 3.3V and 5V and 120mVpp for 12V.

And that PSU has, less surprisingly for OCZ, some very cheap Chinese capacitors.
http://download.orthy.de/reports/ocz550/10.jpg
http://download.orthy.de/reports/ocz550/13.jpg
 
Don't know how you get AC riding with DC but that sounds difficult, AC as the name implies goes above and below 0v(ground).

DC does not fluctuate, the ripple is caused by the full wave rectifiers in circuits being of a poor design.
 
It's not ripple, I think that's his point. And yes you can have a AC voltage on top of a DC voltage (effectively the AC is offset from 0V). What is measured in the article is voltage instability, not ripple, but it's well within the ATX spec.
 
I think he ment the RMS Value of AC and not its peak + 0v - the rms is the value you would expect in a dc circuit, a flat line. The ripple in the ac would be the frequency 50Hz uk mains voltage (or on and off 50 times a second) giving you a ripple you would smooth using rectifier / capasitors etc. if you had a ripple in the dc side it would indicate poor smoothing of an ac circuit
 
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