Fractal Design Dynamic X2 Fans

Soldato
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They have such low pressure ratings they will not be much good behind a grill and filter setup unless they are running at full speed.

What do you what to use them in?
 
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I don't want to use them, was just curious whether they will be stocked and at what price.

What would you recommend using them as then, exhaust? I thought SP only mattered for radiators/heatsinks.
 
Soldato
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What would you recommend using them as then, exhaust? I thought SP only mattered for radiators/heatsinks.
SP is best for any space where airflow is restricted. For me, that includes grilled air intakes, hard drive cages, etc.

These are mediocre airflow fans, about on par with a Noctua NF-S12 fan... so yeah, case exhaust, pretty much.
 
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What ttaskmaster said.

Fan specificcations use open airflow for CFM .. a fan hanging in an open space with absolutely nothing blocking it's airflow. Reality is even a round wire or honeycomb grill restrict 10-30% of a fan's airflow. Obviously the lower it's pressure rating the more the grill lowers the airflow.

Static pressure rating is the maximum pressure the fan is pushing when air stops flowing. 'Static' means stopped, stationary, still, no movement.

While we may use a fan to move air about in really hot weather, I doubt anyone is ever using a fan blocked so it can flow no air .. at least not if they know it's not moving any air. :D

What does this all mean? Well, we need fans that move air when used with the even more restrictive front grills that block even more area and where most of us also have filters to keep dust out of our systems.

Now you asked again 'what does this all mean?' It means case fans that are similar to fans used on restrictive air coolers or quality radiators make the best case fans.

I will also add to all of this that with modern motherboard fan control abilities many (maybe most) of us are now controlling our case fans the same way CPU and GPU fans are controlled .. fan idle when system load is at idle, and speed up as system load / temperature increases. You know, like CPU coolers and GPU coolers have done for donkey's years .. and notebooks/laptops have done forever.

This also means the fans have much less airflow at lower speeds becuase their abilty to overcome resistance drops dramatically when their speed is lowered.
 
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I use NB PL1 as an exhaust fan currently, one of the quietest fans I've used and does the intended job perfectly.

Thanks for that explanation doyll definitely cleared up a few things!

Side fan is an akasa Apache and can't remember front but hopefully a decent SP one!
 
Soldato
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Of my 5 systems (plus notebooks) only 1 has exhaust fan. Al the others are only have intake fans. it's like a good single tower cooler only needing a front fan. Good case layout with good fans means no need for exhaust fans.
 
Soldato
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First I've heard that!

I thought an exhaust for cooler isn't necessary because the case has one!
The science of airflow is Fluid Dynamics. Airflow basically works the same a fluids .. except air can be compressed / expanded more which creates many more variables to deal with.

Our cases are basically like water tanks with the vents being the pipes flowing water into and out of the tank. Tank has to flow as much water out as is flowing in .. or .. as much water must flow as much water as is flowing out.

A cooler inside of case is just another fan moving air. If we don't supply that fan with enough air it will simply pull air from it's surroundings to make up the difference. Problem is this 'makeup air' has most often already been used cooling something else and is warmer, which warms up the air going into cooler, which means it cannot cool CPU as well and we get higher.

What this means is we have to pay attention to not only supplying the case with enough airflow to supply component need, but we must make sure that airflow goes to components and pushes / moves their heated exhaust air away from where the cool air is needed.

Creating these invisible streams of airflow is the hard part. The case is like a pond of clear water with several dirty streams running into it and several running out. If the streams flowing in are nice smooth flow with nothing disturbing them they will create a channel of dirty water from where they flow in to where the flow out with little of it mixing with the clear water in the pond. but if the have things disrupting their flow (like logs, rocks, etc) or are flowing too fast then their flow changes direction and creates turbulence, which disturbs more water, etc. Pretty soon the nice clear water int the pond becomes mixed up with the dirty water the stream is flowing and whole pond is dirty.

I hope that makes sense.
 
Soldato
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Try running a small dirty stream into a bigger clear quiet stream. If streams are slow moving with no rocks logs, etc. the dirty stream will flow a nice narrow path in the bigger clear stream. But if it's a babbling brook. (like I'm babbling) the dirty stream water wil mix with with the clear stream rather quickly.
 
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