Quiet case: critical factors ?

[ggilles]

I'm wandering if I've well understood which factors are leading to a quiet case (or, if not, to the case you'd better throw through the window)

1 - no doubt: fans (CPU, Power Unit, front and rear vents)
2 - no doubt: HDD and other units (CD/DVD)
3 - it is true (efficient): additional plastic covers in addition to steel case

 

[Jhhnn]

Basic case design in terms of resistance to airflow is probably as important as any other factor. With cases that breathe well, very quiet low power fans can be used. Cases that have high restriction need more powerful noisier fans in order to provide the same airflow.

The SX-Antecs are an excellent example of this. The front bezel offers little restriction to airflow, the fanholders are zero-restriction, and the stock stamped fan grilles are about as open as possible.

With the dual rear fan possibility, ducting an Alpha cpu heatsink to a quiet 80mm fan blowing out the back works well, and allows one quiet fan to perform double-duty. I use a homemade version of this:

DUCT

I can't believe that anybody might actually get a patent on this....

 

[jsbush]

So are you saying that with an Antec SX case you can duct the heatsink on the cpu and you wouldn't need a 60mm fan on it? So I could take off the fan on the alpha?

 

[Jhhnn]

Yes, that is precisely what I'm saying. With some thin aluminum sheeting, some 3" aluminum dryer vent and a few tools, the stock alpha shroud can be connected to a 80mm fan mounted on the back of the case.

This is not to say that it is the ultimate in cooling, there is some loss due to the ducting, but my p3e550 runs 143fsb ducted to a PCPower&Cooling Silencer. I back off to 133fsb when the kids are gaming. Obviously, an overclocked AMD would require more of a fan, for sure. Might even have to back off a bit. There has been some in-depth discussion over at the Ars forum.

I'm hoping that Santa brings me a digital camera, and that my DSL with website comes together RSN.....

 

[Alain]

On point 1) you can go with a 90mm fan. You can get the same air flow with a lower RPM = less noise (most of the time). From my experience, I got lower noise this way. Even when I did spent a lots of money on a silent 80mm fan, it always ended-up making more noise.

On point 3) I always thought that my Dell plastics case was a better noise damper that a classic metal casing. I recently put two hard drive, one IBM 75GXP in my Dell casing (no other drives) and the other 75GXP in my A-Top (metal casing). And let my tell you there is a very noticeable differences in the two from the noise of the drives..

My Dell is an old PentiumPro200 (still running) but I thing the newer Dell casing actually comes with some kind of duct system with no fan on the CPU.
Like this case from Fong Kai

 

[Usul]

The PS fan is usually the noisier one!