Cooling Question - Stacked Fans

Trigmaster15

Honorable
Sep 27, 2012
16
0
10,510
Hi everyone,

I just wanted to ask a quick question. I'm trying to calculate the total CFMs going in and out of my case, and I was getting stuck on one part. On the top of my case, I have a 360mm radiator. Beneath it are 3 120mm fans, and above it are 2 200mm fans. All 5 of these fans are blowing or pulling air upwards out of the top of the case. Now when I calculate the CFMs, would I just use the 2 200mm fan CFM ratings, since they are closest to the case-environment interface, or would I use all 5 since they are all working to pull the air upwards? Thanks for any advice/insights!
 
Gains from stacked fans are pretty minimal, although it was a marketing gimmick however many years ago.

You could probably call it safe with just calculating the two 200 mm fan ratings, since airflow through a radiator is rather reduced anyway.