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CFM vs Static Pressure

Last response: in Overclocking
a b K Overclocking

CFM vs Static Pressure

I'm just not sure. I thought that cfm and static pressure are directly proportional so that higher CFM always means better static pressure. But when looking at reviews for water cooling, there seems to be a more significant difference between cfm and static pressure. Can anybody clarify for me?

More about : cfm static pressure

its not necessarily true that they are proportional. For a basic example, a high RPM smaller radius fan pushing the same CFM as a fan twice the size of the same design will likely have completely different static pressure. The smaller fan would likely perform better in a higher pressure environment as it is producing more pressure initially, forcing more air through a smaller opening. But there are other factors such as the power of the motor, fan type, blade angles/curves etc, etc.
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a b K Overclocking

Ok. But between 120mm fans, what will determine cfm and static pressure?
My scythe fan had 1800rpm and 100+ cfm but reviews said it had low static pressure.
The gentle typhoon fans have 3000rpm and lower cfm but reviews praise it for its high static pressure.
The difference in design i see is that the typhoon has more but shallower blades while scythe has fewer but steeper blades.

So does higher rpm, shallower blades, or more blades usually give higher static pressure?
a b K Overclocking

RJR said:
Check FPI of radiator,
denser fins = use higher pressure fans
lower fin density = concentrate on cfm

:p  I just saw that.
So by denser fins do you mean more fins? :p