Quote Originally Posted by ChuckM View Post
I think it would be better with the psu fan up, blowing into the case like would if it were top mounted. Anyway here's the manual and it says if the fan is on the bottom of psu to point it up.
http://www.antec.com/pdf/manuals/300_EN%20manual.pdf
PSU fans do not blow air into the system. They suck air out of the system. Also there is no real upside down or right side up to a PSU. You face the fan in the dirrection is will be able to pull the most aitr into the unit.