Done. Noise level much lower. There was also a sympathy hum from the rear panel after installing the S12A FLX ... even before I plugged the fan in. I loosened the screws a little and that went away.
Actually - what I have isn't a S12A FLX ... it has 4 pins. How do I tell the difference between a NF-F12 PWM, NF-P12 PWM and a NF-S12A PWM?
Duh ... by looking at the sticker on the back .
Edited by ruffhi - 9/29/15 at 7:32pm