Quote:
Originally posted by bigben2k
I too would like to see the 12V line remain within specs, which is +/- 5%, with 100 mv max ripple, expecially since I'm thinking of using 2 of them 
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Although I didn't check in every case, I don't believe the 12V rail was ever out of spec anywhere other than on the drive line connected to the pump. (Although 11.5V is certainly low for a lightly loaded 12V rail. I'll have to adjust it.)
The ripple spec refers to changes in the output at the PSU's switching rate. As lightly loaded as the rail was, there is no "ripple" to be seen.
As far as the high frequency transients are concerned...
With the 0.1uF cap installed, I suspect the CPU will cause worse transients on the 12V rail at the motherboard, than the pump does. However, for those who want more significant noise suppression, a ferrite bead core on the 12V line leading to the pump could help. Something like Digi-Key part# 240-2067-ND might do, although I can't find DC current specs on it, and it may be saturated by the 1.5A current draw of the pump to the point it is useless.