[Marsdy]

I’ve been using MacsFan Control for a year.

It does help with reducing HDX fan noise. I’m on a 7.1 Mac Pro and the HDX card is the only thing I can hear. I set the Mac fan nearest the card to 1000rpm (one of the three big ones at the front of the chassis.) You can hear it but it’s a LOT less intrusive and annoying than the high pitched HDX fan. The HDX fan still comes on under heavy load but a lot less frequently.