static pressure and CFM????

Geekazoid

Geekazoid

Geekazoid

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whats the difference??? i was thinking of buying the Scythe Kaze Jyuni 1900RPM Slip Stream 120mm Fan @ 110CFM but was told that these fans are crap for my True 120 extream as they have crap Static Pressure???? and that Noctua P12 fan was better as it had higher Static Pressure but less CFM so was better for heatsinks... what is the difference as this is confusing???
 
Let me try and explain like this

cfm = how much air a fan will shift

static pressure = how hard it shifts it.

So for case fans, static pressure is pretty irrelevant and fans with higher cfm will do best.

For heatsinks and radicators you are trying to push the air through small spaces. This drops the cfm measured at the other side of the cooler/radiator. The lower the static pressure, the more the drop.

Noctua S12 fans can hardly push through a heatsink and in reviews register below the measurability of the sensor.

So yes you can have a fan with a lower cfm but higher static pressure which when run on a heatsink/radiator it will outperform a higher cfm fan with a lower static pressure.

Have a look at some reviews were they test using a cooler or radiator especially the madshrimps ones to see what I mean.
 
thanks

made it a wee bit clearer i was just about to order 2 Scythe Kaze Jyuni 1900RPM Slip Stream for my True but then stumbled across this static vs CFM argument...

[edit] also whats the best fan that you guys recommend on an True heatsink in push pull configuration taking into account CFM and Static Pressure
 
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Scythe S-flex 1600s. Used them on my one.

Whether push-pull helps depends on your case. Specifically if you have a 120mm exhaust right behind the true anyway, adding a pull fan will leave very little spacebetween them and this inteferes with airflow. I've seen an absolute maximum of 5 degrees improvement from using a second fan on a bench, and in my case I get the same temperatures with one as I do with two.

The alternative is just find one reviewed as having high static pressure. I like the scythes, good general purpose fans.
 
Sharkoon silent eagle 2000's, i had theese on a TRUE black cooling a 3.8ghz q6600, switched them for the 400-1200 pwm versions, gonna put the original 2000 rpm models back on the cooler and run em of a fan controller.
 
Yep mate, thats the ones, i think the whole golf ball thing is a sales gimmick, but i can guarantee they shift a lot of hot air. When your air cooling a cpu with normal fans things can get toasty, the silent eagles are the top of the range, after that your looking at delta fans with extreme cfm and noise, the nice thing about the sharks are they have very good positive pressure, theyre well priced and they look great, not like noctua fans, great cooling but ugly as sin. Ive tried quite a lot of fans lately, scythes, noctua's, yate loons etc, the sharkoons were the best of the lot.
 
setter said:
Yep mate, thats the ones, i think the whole golf ball thing is a sales gimmick, but i can guarantee they shift a lot of hot air. When your air cooling a cpu with normal fans things can get toasty, the silent eagles are the top of the range, after that your looking at delta fans with extreme cfm and noise, the nice thing about the sharks are they have very good positive pressure, theyre well priced and they look great, not like noctua fans, great cooling but ugly as sin. Ive tried quite a lot of fans lately, scythes, noctua's, yate loons etc, the sharkoons were the best of the lot.
Click to expand...

+1 got 5 of them
 
Geekazoid said:
i was thinking of buying the Scythe Kaze Jyuni 1900RPM Slip Stream 120mm Fan @ 110CFM but was told that these fans are crap for my True 120 extream
Click to expand...

Lack the static pressure for heatsinks so as mentioned not ideal for CPU coolers. However they do work a treat as case air extractors, fairly noisy when going full tilt though so I can only recommend them been used via fan speed control. I use a combination of Jyuni 1900RPM and Eagle 2000RPM.
 
as a matter of intrest i have a antec 902 case the tri cool fans what cfm are they pushing at full tilt?? as im thinking of replacing them... if i do replace them do i have to cut the cable which lead to the fan controllers???
 
Geekazoid said:
as a matter of intrest i have a antec 902 case the tri cool fans what cfm are they pushing at full tilt?? as im thinking of replacing them... if i do replace them do i have to cut the cable which lead to the fan controllers???
Click to expand...

That info should be in your Antec 902 manual, my Antec 1200's manual has that info about my fans.

Here just in case you dont have your manual
 
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