for my aerocool strike x casing i have:

2 x 120mm fan in front for intake
1 x 120mm fan below for intake
1 x 120mm fan on the side panel for intake
1 x 140mm fan on top for exhaust
1 x 120mm fan behind the casing for exhaust
2 x 80mm fan attached with cpu heatsink for cpu cooling one intake one exhaust
1 x fan that comes with hd6850 GC

and all the casing fan has red led.