How do i place the power supply in a computer Case?

[BearHunter1]

my case power supply goes on the top of my computer case. that much i know. But a lot of the tutorials i watch show you place the Power supply fan faced down. Said something like it sucks up air and blows out the back.

what i am asking is do i do the same (as in i place the Power supply fan facing the top of the case) or do i face the fan down facing the bottom of the case excepts its on the top instead of on the bottom.

 

[N3rdR4ge]

heres the deal.

if the top of your case is 1.vented 2.dust filtered 3.can support the psu fan facing top (aligns with screw holes with fan up) than face fan up.

If any of those 3 things i mentioned are missing, face fan down.