The speed of those PAst fans is low compared to the airflow. Nice fans!!
It seems that once again I saw a post late
I was going to recomend changing the PSU. I have a noise activated led, which used to be always lit, and then I changed my PSU to an Antec, and the led now only lits when I talk
I also use Antec fans. They are a bit noisuer than those, bit they regulate speed according to the temperature. The PSU also does this.
To top it off, the PSU also has a special line of molex just for Fans, and with the included 5 1/4 bay, you can regulate the fans speed. I actually keep speeds up, so the PC can be cooler. Have in mind that I have 6 hard drives, all are 7200 rpm, and 3 of them are 160 GB which produce lots of heat. MY PC is a jet, but then, I can turn down the noise if I want, in exchange for some degress. I keep the PC at 35 c usually, but even with the fans @ low RPM the temp doesn't go over 45. (talking about CPU)
Have in mind that I have aluminium case thought. With my previous case the temp were higher.