Question about making a video card with fan quieter

It will never be as quiet as a completely passive cooler but after market coolers notably the Zalman VF700, VF900 and Arctic cooling NV Silencer, Accerelo coolers are almost silent and offer much better cooling then nvidia stock coolers.
(by almost silent you have to try and hear them over your case fans)
Also not quite as easy to install in some instances but the Masscool/Sytrin KuFormula VF1 plus is also a excellent cooler.

If I was to pick one cooler it would be the Zalman VF900 (on sale) I have one and is very quite just be careful due to they can be quite pricey off sale.

http://www.tomshardware.com/2006/08/30/vga_heat_pipe_cooler_roundup_2006/
The zalman take some knock's here but the nvidia 7900gt is a much cooler running card compared to the ATI X1900XTX. Also the KuFormula does exceptionally well in THG's cooler round up.

And if makeing your computer quiet is your goal check out http://www.silentpcreview.com/

Since the card you are interested in is an ASUS one, it will be quiet.

I have experience from a fanned ASUS 7300GS. It was quiet.
Much quieter than an equivalent Inno 3D card.

If it ain't quiet enough for you after you buy it, use an ARCTIC ACCELERO X1. I got a NEW boxed one sitting here. If you are in UK, £15 incl. p&p. Bought for a 6200 and from the box, it looks bigger than my card!

Otherwise, disconnect the fan. And have a 80mm case fan blowing air to it directly across.