PSU fan facing UP or down?

Solution
If there are ventilation holes at the bottom of your case, orient your PSU so that it's fan takes in air from there. I think that's preferable than using the PSU fan as an exhaust fan to move the warmer air in the case over the PSU components for cooling.
If there are ventilation holes at the bottom of your case, orient your PSU so that it's fan takes in air from there. I think that's preferable than using the PSU fan as an exhaust fan to move the warmer air in the case over the PSU components for cooling.
 
Solution