Ok I finally got everything together and running on air, I'm very happy except for the fact that i cant actually use my gaming rig to play games due to an audio problem. I'm hopping someone here has some advise =(
I like D as it will create a positive pressure that will help with dust. But B would almost be the same. I just like pull a little better but that also may be dependent on the fans you are running as well. Just my two cents.