I have a question about fans and airflow, specifically related to processor cooling. I have a large heatpipe/radiator on my processor which came with one fan installed that blows air across the fins (a push fan). The assembly is set up to be able to add a second fan on the opposite side to pull air out of the radiator (push-pull configuration). They sell the cooler pre-installed with both fans for an extra $20 or so. What I’m curious about is if this second fan is actually that useful, or is it mostly marketing hype? My thought process goes like this: The initial fan moves 120m3/h of air. If I put one of these on, it will push 120m3/h into and across the cooling fins. If I now put a duplicate fan pulling from the other side, it's going to pull that same 120m3/h that the first fan pushed into the fins. It would have more power (i.e., if the air were suddenly thicker and harder to move) but would not pull a greater amount of air or move it any faster. Am I right in my assumptions or totally off base here?