ok, after my true power PSU bit the dust yesterday (with a voided warranty unfortunately), I grabbed the two fans and started experimenting (hey, they're cool looking). The intake (92mm) is noticeable @12v, and quiet @7v (though still a little louder than pabst). The 80mm is deafening @ 12v (though pushing a lot of air) and still loud @ 7v. It almost seems like it's louder at 7v than it was installed in the PSU (I'm guessing the antec controller undervolted lower than 7v). Regardless, there are big gains to be realized by using a different PSU or changing the fans.