I have the 9700, and it's virtually silent. I'm using a Zalman fan controller on the lowest fan speed.

If you use the Fan Mate controller that comes with it at the lowest fan speed, then it'll probably be just as "silent".
My temps are 30 idle and 40 load with my quad. BUT, I've got an Antec Three Hundred case, so there's a lot of airflow. I used to have an Antec Nine Hundred with it, but I decided to get the Three Hundred because it's got the air filters in the front. The Nine Hundred sucks because of the massive collection of dust; no fan filters in the front...