High Static Pressure Fans

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celwin

[H]ard|Gawd
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Oct 18, 2006
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What exactly is the starting point in mm/H20 that a fan is considered as having high static pressure? Everyone says get a high static pressure fan for rads, but no one ever gives a mm/H20 range as to what constitutes high.
 
There isn't an exact value of static pressure that is defined as the starting point for "high static pressure". You're just looking for fans that are in the higher range of what you're able to buy. Even if you can't find manufacturer specifications that give static pressure, you can usually tell what a fan is designed for (more airflow or higher pressure) by looking at the fan's design. Larger fan blades with a higher rake will generate higher static pressure whereas fans with lower rake won't generate as much static pressure.
 
Goty said:
There isn't an exact value of static pressure that is defined as the starting point for "high static pressure". You're just looking for fans that are in the higher range of what you're able to buy. Even if you can't find manufacturer specifications that give static pressure, you can usually tell what a fan is designed for (more airflow or higher pressure) by looking at the fan's design. Larger fan blades with a higher rake will generate higher static pressure whereas fans with lower rake won't generate as much static pressure.
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What is a "rake?"
 
x509 said:
What is a "rake?"
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How much the blade curves back. Rake increases the fan's leading edge area vs. a straight bladed fan. It's like cramming a bigger fan blade into a smaller area.

You also want to find fans that have a very small gap between the blade tip and the fan casing and fans that have overlap between the fan blades. If you look at a Gentle Typhoon head on, you pretty much only see fan blades and no gaps between them.


If you're looking for a metric, just look at the pressure ratings on Gentle Typhoons. They are the ideal 25mm thick fans, every other fan in that size is measured against them.
 
When I looked 1.5 weeks ago I could not locate any AP14 models. I do not want the AP15 ones. . I have since find some higher pressure fans at a much cheaper price point of any of the ones mentioned thus far. Masscool BLD-12025V1R
 
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celwin said:
When I looked 1.5 weeks ago I could not locate any AP14 models. I do not want the AP15 ones. . I have since find some higher pressure fans at a much cheaper price point of any of the ones mentioned thus far. Masscool BLD-12025V1R
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Can't seem to find any reviews on the Masscool, not sure if the manufacturers ratings are true.
 
celwin said:
When I looked 1.5 weeks ago I could not locate any AP14 models. I do not want the AP15 ones. . I have since find some higher pressure fans at a much cheaper price point of any of the ones mentioned thus far. Masscool BLD-12025V1R
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If there's no 3rd party test data, there's no proof they are higher pressure.

Which Gentle Typhoons did you want? There's other stores out there.
 
EarthwormJim said:
If there's no 3rd party test data, there's no proof they are higher pressure.

Which Gentle Typhoons did you want? There's other stores out there.
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I think they are the same fans (or very close) as the CM R4's which are just down right bad.

EarthwormJim said:
I wouldn't really directly compare 25mm fans to 35mm fans.
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I would, so does Martin, many 38mm fan in his tests and all of them are beat by the GT's other than when you start getting into ultra high rpm, and even only then because he only has up to the AP-15's, nothing higher, I would be willing to bet if he did the GT's of the same rpm as the NMB and deltas the GT's would give them a run for the money if not win.
 
BlueFireIce said:
I think they are the same fans (or very close) as the CM R4's which are just down right bad.



I would, so does Martin, many 38mm fan in his tests and all of them are beat by the GT's other than when you start getting into ultra high rpm, and even only then because he only has up to the AP-15's, nothing higher, I would be willing to bet if he did the GT's of the same rpm as the NMB and deltas the GT's would give them a run for the money if not win.
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Not everyone can physically fit them. That's why I wouldn't directly compare them. If you have the space for a 38mm fan and don't care about noise, then yes why even bother looking at 25mm fans.
 
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I dunno folks. I'm running a single D5, two 680s, a full cover mobo block and a CPU block with 2 480 rads, and I"m overclocked to 4.5ghz. GPUs run about 32*C under load and the CPU hits about 45*C - with 4 GT AP15s per rad. I'd say that's about all the performance I need. I could easily fit 38mm fans push/pull in my case, but why would I want that when the AP15s do it all in near-silence?
 
silent-circuit said:
Only if you use a high speed variant or don't put them on a fan controller. http://www.sidewindercomputers.com/paaxfa1.html

I use several of the mid speeds with a fan controller and they're some of the quietest fans I've ever dealt with, while still moving far more air than anything else I've seen for the same noise.
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If you refer to this table: http://imageshack.us/f/87/fantable124.png/ you will find that the scythe's outperform the panaflo for noise levels at comparable cfm when mounted to a radiator.

I'd venture a guess to say that the scythes are probably quieter because they probably have better static pressure, and therefore the cfm losses when pushing through a radiator are less than the panaflo, thus the panaflo would have to spin faster than the ap-15 in order to achieve the same flow in cfm through the radiator. But hey, thats speculation. All i know is the scythes are quieter at 30 and 35 cfm (when pushed through a rad)

also, the panaflos click pretty bad at low rpm's. http://www.youtube.com/watch?feature=player_embedded&v=RpGB0QRY4Fw#

Honestly, i searched far and wide looking for a fan that wasnt the scythe for my build, but in the end it just happened to be the best performing. =/
 
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EarthwormJim said:
If you have the space for a 38mm fan, then yes why even bother looking at 25mm fans.
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Because the 25mm GTs perform better, they also have a far smoother motor/bearing. That's what I was saying. ;-)
 
thesecond said:
If you refer to this table: http://imageshack.us/f/87/fantable124.png/ you will find that the scythe's outperform the panaflo for noise levels at comparable cfm when mounted to a radiator.

I'd venture a guess to say that the scythes are probably quieter because they probably have better static pressure, and therefore the cfm losses when pushing through a radiator are less than the panaflo, thus the panaflo would have to spin faster than the ap-15 in order to achieve the same flow in cfm through the radiator. But hey, thats speculation. All i know is the scythes are quieter at 30 and 35 cfm (when pushed through a rad)

also, the panaflos click pretty bad at low rpm's. http://www.youtube.com/watch?feature=player_embedded&v=RpGB0QRY4Fw#

Honestly, i searched far and wide looking for a fan that wasnt the scythe for my build, but in the end it just happened to be the best performing. =/
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Panaflos have an outdated fan blade design, that's why Gentle Typhoons do so much better despite being a thinner fan.
 
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