I recently built a gaming pc and all I need now is Windows. While waiting, I was watching some more videos about how to build a pc, and a few of them show the PSU's fan pointing down and a few show the fan pointing up. Can I do it either way? I made mine point down.
If it is bottom mounted you want the fan pointing down. if it is top mounted and you have ventilation up top you want it pointing up. No ventilation it has to be mounted facing down.
The reason is the fan is the intake and you want it to pull cold air from outside the case if possible, not hot air from inside. But it CAN be done either way, and some times you have to if there's no ventilation