620HX and P180 case

[KoHaN69]

Hello, I have a question about the 620HX and P180 case
which orientation is most optimal for longetivity fo the psu and/or lowest noise: the 120mm fan down or up?

[zanzabar]

i have my tx750 with the fan facing down

[KoHaN69]

well, the way the 620hx is designed, the pcb is on top, with sinks facing down
and as for as my knowledge of physics goes, the pcb on top with heatsink facing down is less effective than a pcb on bottom with heatsink facing up

so thats why i thought flipping the psu upside down should improve cooling peformance