If you run it with a Mobile Athlon XP at stock or understock voltage, you can get away with using a low speed case fan; mine was incredibly loud because the I.C.E. system is not the best system on Earth, not even close, and overclocking it as I was, I had to run a fairly fast fan. The video card was also quite loud, but it won't be an issue in your case.
Keep in mind, however, that SN41G2V2 has a serious hard drive noise issue as well, if everything else is quiet. The hard mounting and aluminum construction combine to cause this condition; my recommendation would be to suspend a laptop drive in it; the cage is far too tight to suspend a 3.5" drive, but a 2.5" drive with its smaller size, lower heat output, higher heat resistance and lower vibration would be an optimal choice to suspend within the Shuttle.
Also remember that the northbridge is actively cooled and there probably isn't enough space to fit a decent passive cooler on there (particularly considering you will be utilizing the onboard video, which will mean even more heat from the northbridge). I do not recall if my northbridge cooler was really loud or not, but that's mostly due to the rest of the system being on the loud side. The speed of that northbridge fan is controlled by the motherboard, based on temperatures.
The SilentX PSU is a massive improvement over the older PSU, MUCH quieter; however, whether as I said, it was hard to hear much of anything over the din of my case and video card fans.
Good luck to you, my friend, but might I recommend instead of the SN41G2V2, an Antec Aria with a mATX Socket A board with the Mobile Barton? Even if it comes with an active cooler, you can try it out and see if it's loud or not; if it's not loud, leave it and if it is loud, at least there's room enough to use a decent replacement sink like a Swiftech MCX-159 with the fan removed or maybe Zalman's passive cooler, which I've no hands-on experience with, but keep in mind Zalman does not recommend using their cooler on a northbridge with onboard video.
The fact that the Aria's PSU uses a 120mm fan alone makes it easier to mod for quieter operation, if it even makes much noise. Plus, the Aria is much more conducive to softmounting/suspending a 3.5" drive, which would save money (2.5" drives have higher $/GB cost). Those multilayer sound dampening panels look quite appealing, too.
EDIT: PS I also want to just say that the Aria provides much more flexibility in choosing the cooler for the CPU, so you could utilize something better than the darn I.C.E. cooler, like an SLK-900A with a quiet fan.
Contributing Writer, SPCR
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