Replacing the fan on Chipset

Bought a while ago following graphics cards:
Gigabyte GeForce 8800GT 512MB GDDR3, PCI-Express 2.0, 2xDVI/HDCP

For this graphics card, followed it with the following fan:
Zalman VF830-Cu GPU cooler

When it comes to the graphics card, I am very happy. While cooling has been cruel. However, it is a small problem. I have tried to build a silent PC, and if I "turn off" graphics fan so it would be nearly silent. Unfortunately is not the case when it spins. Thought that this fan would be quiet but later read to the sounds part. In any case, if it spends on a very quiet computer. My question now is:

If I buy a new fan, which I want to have as good cooling as I have before, but much, much quieter, what should I buy?

Hope you have some good advice for me.

Buy a Zalman fanmate and connect :)

Hmm, it is sufficient then...will not only lead to the graphics card, too hot when I lower speeds (guess it does)?

Well, has the same problem that you fixed with a 8800GT, I will buy a passive cooler from the Artic cooling. The units Aceleero S1 or something similar. It seems completely sovereign in the cold completely silent and you may then turn on a fan at the run in 5v for virtually silent with excellent cooling. From the cooler he had before 55/84 and after 40/53. And without the extra fan is totally silent!