Suggest new fan placement?

[smalltech]

Q1) Is adding a 120mm fan to A or B better?
Q2) Is adding two 120mm fans to A and C better? or A and B better?

The blue fonts are 120mm fans I intend to add for air intake into casing. I intend to add either 1 or 2 fans.

The red fonts are fans that are already in my casing CM 690 II Advanced

Other suggestions?

 

[madchemist83]

I would add 2 140s as side intake and 120 as bottom intake, slot A.

 

[Gam3r01]

Add in the bottom fan labeled A, fan B would be disrupted, and fan C is pointless as it dosent bring in new air.
I however, disagree with the above. Cases work best with a two dimensional convection style airflow. Cool air in the front/bottom, hot air out the rear/top.

Side fans add in a third dimension to this, as disrupt flow more than they help. Unless you are using several reference style blower graphics cards, these fans hinder airflow.

 

[smalltech]

Add in the bottom fan labeled A, fan B would be disrupted, and fan C is pointless as it dosent bring in new air.
I however, disagree with the above. Cases work best with a two dimensional convection style airflow. Cool air in the front/bottom, hot air out the rear/top.

Side fans add in a third dimension to this, as disrupt flow more than they help. Unless you are using several reference style blower graphics cards, these fans hinder airflow.

So do I add fan A and B, or only add fan A?

 

[Gam3r01]

Only A

 

[smalltech]

Just to be clear, my intention is to put the fan B blowing towards the left in the image. (air blowing towards the back of the casing)
Direction of fan B air flow
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[smalltech]

I have one 140mm PWM fan and two 140mm normal (non pwm) fans, should I put the 140mm PWM fan at the front, top (nearer back) or top (nearer front)?

What software is good to control PWM? First time using a PWM fan.

 

[madchemist83]

You can disagree all u want, facts r facts.
http://www.bit-tech.net/hardware/2012/02/10/the-big-cooling-investigation/1
Two dimensional air flow ? It is 3d by default, side and bottom fans keep constant air flow connected with exhaust. Front fans are not powerful enough to push air far enough so you create stagnant air.
Also I would always go for bigger fans like 140s on the side then 120s upfront.
Speedfan is a good software to control fans.
You can go negative pressure which technically will keep ur pc cooler but introduce more dust.

 

[smalltech]

Lets say orange arrows will be where the fans are, and air direction arrows for my casing.
Are these placements good since the B fan will help push the air (as madchemist83 mentioned that Front fans are not powerful enough to push air far enough)

So the 140mm PWM fan should put in front? ( I have only 1 PWM fan, all other are normal fans)

 

[madchemist83]

How many hdds/ssds u have in the bracket ? Location b would make sense if there r a lot.
Otherwise A and sides. U really don't have any components in the current path of air that needs cooling, blocking airflow by hdds reduces efficiency.
What's the rest of your rig btw and how is ur cpu cooler fan positioned ?