120x38mm fans?

[Jeb!]

I've been shopping for fans recently and have been wondering about the potential of 38mm thick fans, as are commonly seen in high speeds intended for server installations. It's common knowledge that 15mm thick fans represent a drastic performance decrease over 25mm designs, so going by that logic, wouldn't 38mm fans further increase performance per rotation and thus silence?

These are the kind of fans I'm looking at:

http://www.sidewindercomputers.com/pa12mesp.html
http://www.sidewindercomputers.com/de12trbllows1.html
I've also heard good things about San-Ace, although finding a legit source isn't as easy for them.

I have a fan controller that could spin them down. The only downsides I can think of are the wide-diameter hubs intended to handle the high speeds but blocking some airflow, and the fact that the bearings, etc. were not designed with silence in mind. Also I'll admit I have a love for all-business server aesthetic over gamer bling.

Does anyone have any experience with these fans?

P.S. now that SPCR seems to be dead, what is your favorite source for fan reviews?

[CA_Steve]

What we don't know is the minimum speed for these fans. They might be able to push more air at a given rpm, but if they can't get down in the sub-600rpm range, they won't be quiet.

[lodestar]

Silverstone have a 38mm fan, the SST-FHP141-VF and it is PWM with a stated range of 500 to 2000 rpm. It has dual 120/140mm fittings that Silverstone say is "...compatible with any 120mm or 140mm fan slot...". Full details are here. I note that this fan has a switch to reverse the direction of airflow which may be a unique feature.

[Olle P]

From a very general point of view my experience says:
* Thicker fans generate more pressure at a given maximum (zero pressure) flow rating.
* Thicker fans generate more noise at a given zero pressure flow rating.

Given that you have fairly restrictive air paths with dust filters and other stuff a thicker fan may generate a specific amount of air pressure (and thus flow) at a lower noise level that a thinner fan.

[lodestar]

Yes, it could be that the Silverstone SST-FHP141-VF in PWM mode with a minimum speed of around 500 rpm might well be a star performer as a CPU cooler fan. However there is no data available to support this either way. The only data there is on this fan, from the DV Tests review shows that it is fairly aggressive in voltage mode (1350 rpm at its starting voltage of 7V, 1725 rpm at 9V and 2115 rpm at 12V). And noisy of course. But I suspect the user base for this fan is far more likely to be those who just want increased airflow regardless of the noise.