optimal airflow?

[Guest]

I have a Aerocool ds cube design case
It supports a large 20 cm fan in the front that blows air inwards at a speed of 500 rpm

in the end of the case there can be a 12cm/14cm fan be attached, and in top of the case 2 fans can be attached of 12cm/14cm

 

There is a 20cm infront of the case as intake with a 500 rpm speed
then I have 2 82mm fans on my coolermaster tx3 cooler for my cpu that blow the heat to the back of the case.

 

but now, I have 3 fan slots left and 1 12cm fan
What would be the best position to place it?

in the rear as outtake?

or in the top as intake or outtake?

 

[aircrafttech]

@voylin Rear outtake. Best overall airflow.

[WereCat]

My opinion.

If air cooling CPU:

Intake front and if possible bottom and exhaust back and top left open with no fans because warm air will go naturally up.