I know that i read somewhere about stacking case fans for improved air flow. this is my take on the idea. I know the CFM for 3 of the fans and the PSI for only 1 of them the top one is 38.6 CFM .16 PSI. 2 of the side fans (the ones with the grills are 35.64 cfm. i have each fan separated from each other with cardboard and hot glue on everyside except the direction i want the air to flow. i want to know if you guys think that this improves performance.

Your design generates a significant amount of turbulence, thereby reducing the sum pressure and velocity. A single fan is likely 'better'.

Is your goal to create the highest pressure differential or the greatest velocity?

See: http://www.thescienceforum.com/physics/11917-air-flow-dynamics-best-possible-cfm.html

isnt more cfm better than more pressure?

>CFM = >noise

It depends. If the system is closed (a PC case usually is not), a greater pressure differential will dissipate more heat. Bad science (and open systems) cause most of us to use higher CFM fans, often in multiples, to move more hot air. Moving hot air around does not necessarily dissipate heat.

Pressure differentials always create air flow. Air flow does not always create pressure differentials.

Air cooled video cards - the fan blows air over the GPU heat sink. The surrounding air accumulates heat. The heated air is blown over the GPU heat sink. Unless your 'CFM-centric' air flow design specifically routes that air pocket out of the case, you get a GPU fan spinning at the top end with a cooling effectiveness at the low end. A pressure-centric air flow design will not develop such pockets.

CFM is important, but it is only one factor.

actually i was going to mount this on the side ot the case

Dissertation withdrawn.

It looks cool.