So yours are super silent from switch on and don't get quieter in windows? Maybe you can't hear it in your case with other fans etc? I've got the Silverstone FT02-W with fans on low, so I can hear any loud component.
Yea I will only hear it when I set it to 50% manually. only fans that I have are the 3 big ones from the haf x and 2x 120 fan for my antec 620 so im pretty sure the card doesnt go 100% during power on