Question Push pull with different rpm fans

[Jayant Arora]

I have 3 x 2000 rpm fans
And 3 x1200 rpm fans can i use them together in push pull config, say 2000 rpm as push and 1200 as pull or vice versa ? Or it won't matter putting 1200 as pull rather just put 2000 as pull only ?
Will it going to put too much load on slower ones and burn them out,
I am No cooling expert It will be an
Experiment,pls suggest.

 

[Darkbreeze]

The faster fans, so long as they also have a higher overall CFM, MUST be on the back in the pull location. Otherwise their potential is not only wasted because they will be trying to push against the restriction of a slow fan that just becomes a blockage, but if they are not extremely high static pressure fans it might also tend to drastically shorten the life of the fan motor.

Fastest/highest CFM fans go on the backside as pull. Slower/higher static pressure fans go on the front as push. Doesn't matter whether that's for the case itself, or a heatsink, or a radiator.

 

[Encryption+]

Yes as Darkbreeze mentioned above the RPMs of the fans are not as relavent as the CFM of the fans. There are plenty of instances where a higher RPM fan still has a lower CFM than a lower RPM fan. An example would be the two below both are 120mm fans, but the lower RPM fan still moves more air than the higher RPM fan.

5200 RPM fan with 240 CFM
6000 RPM fan with 210 CFM

How many fan vents does your case have? Some like my Phanteks have vents on the top as well, which could give you some more options.

 

[Jayant Arora]

The faster fans, so long as they also have a higher overall CFM, MUST be on the back in the pull location. Otherwise their potential is not only wasted because they will be trying to push against the restriction of a slow fan that just becomes a blockage, but if they are not extremely high static pressure fans it might also tend to drastically shorten the life of the fan motor.

Fastest/highest CFM fans go on the backside as pull. Slower/higher static pressure fans go on the front as push. Doesn't matter whether that's for the case itself, or a heatsink, or a radiator.

Just to mention 1200 rpm fans are rated 20.5 CFM and 2000 rpm fans rated 45.6 CFM.

Ill try what you say, let see what happens...

Well i'll try that for sure

 

[Darkbreeze]

WHAT are these fans going on that require a push pull arrangement? Is this a CPU cooler? A radiator? What exactly?

 

[Jayant Arora]

WHAT are these fans going on that require a push pull arrangement? Is this a CPU cooler? A radiator? What exactly?

Well not a radiator just to fit in the case as is, case came with 5 x 1200 rpm fans and are quite slow so i bought 2000 x5 rpm ones and now i have extra 1200 rpm fans .

 

[Darkbreeze]

There is ZERO advantage to using a push pull arrangement at any case fan location. There are intake fan locations (Front, side, bottom) and exhaust fan locations (Top, rear) and that's how fans should be used for case fan locations.

Push pull should only ever be a consideration, and honestly the benefits are there but there aren't tremendous, when using fans on a heatsink or radiator. Putting two fans as push pull in an intake or exhaust fan location will do nothing except probably make things worse.

 

[Jayant Arora]

There is ZERO advantage to using a push pull arrangement at any case fan location. There are intake fan locations (Front, side, bottom) and exhaust fan locations (Top, rear) and that's how fans should be used for case fan locations.

Push pull should only ever be a consideration, and honestly the benefits are there but there aren't tremendous, when using fans on a heatsink or radiator. Putting two fans as push pull in an intake or exhaust fan location will do nothing except probably make things worse.

Ok i still wanna try once with pair of fans 1200 + 2000 at front stacked, both intake and not too close around 12cm apart, let see..

 

[Darkbreeze]

Temps will likely go up, rather than down, and noise levels will likely double.

 

[Jayant Arora]

I see you might be thinking that fan i mentioned 2000 rpm would rotate hot air inside the case dissipated from components, i thought that out already, my case has too much length than height that's why i dared to buy more rpm fans to get more pressure and cfm, and i kind'a modded my case already removed all top drive cages and put those stacked fans in that like in tunnel 1 in and 1 at out scenario, so only one path for air to go inward direction and not top bottom or sides, since top drive body still holds it makes a tunnel/went, It blasts air directly over the cpu cooler, i also added 2 more fan at rear for exhaust, I have 3700X on stock cooler and I tested that, well temps are better now, than before like 5'C better, and also i gained some performance gains, ~4166mhz all core boost with pbo enabled and no manual oc, before it was 4060 Mhz and temps peaking at 78'C -80'C (15 mins aida x64 Test) now it maintains at 72-74C for the same test. Massive gains on vrm temps from 60.C to now 47'C.
Idle temps also improved now from 40-55 to 37-42'C. Now i have like toatal 11 case fans installed, i'm bit happy about it.
Any way i can test air flow is wrong ? Do you want me to test more.

 

[Darkbreeze]

Can you create a diagram showing exactly how you have these fans arranged?

 

[Jayant Arora]

Can you create a diagram showing exactly how you have these fans arranged?

Yea will take some time so pls stay tuned..

 

[Darkbreeze]

Ok.