I have been thinking about airflow the other day and i just want to make sure i got a few things right. For this case, let us assume that all fans are equal and that we don't care about dust and positive/negative airflow. Lets say all fans are 10 cfm. - If we put 1 fan in and 1 fan out, we would have a total airflow through the case of 10 cfm. - if we put 2 fans in, we would have a total airflow of 20 cfm - if we put 2 fans out, we would have a total airflow of 20 cfm If what i wrote is indeed true, purely for airflow and lowest temp, easiest way to achive this would be to get all fans to blow in the same direction and make sure you get enough holes for the air to either get in or go out ? Again, for the sake of the argument, let us forget about the dust and purely think about airflow and temps.