Any idea on if these are noisy on the fan, whine or high-pitched buzzing fronts (when on or off)?
This will probably give you an idea on what the RM series fan curve looks like
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As for the "Coil whine" or high pitch/buzzing noise, here is a good read on how we have addressed that issue with the RM series;
http://www.corsair.com/en/blog/there-is-more-to-psu-noise-than-fan-noise-how-we-fight-coil-whine-in-the-rm-series-power-supplies/