Thansk for responding. I did try fitting the fan such that the big fan faced downwards towards the CPU. But the drilled screw holes on the power supply as well as the case wouldn't fit at all.
Whenn I turned it around the way it is right now, it fit perfectly. So I assumed that the power supply was designed suck in air from the top either through a case with hole on top or through the gap between the ceiling and the P/S.
The big fan is an intake fan not an output fan, the air exhausts out the rear of the power supply, I don't know what kind of case you have, but I've got the same power supply with the big fan exhausting air from over the processor, you may need to order an adapter to be able to turn it over, or break out a drill, and drill the holes you need in the case, thats what I'd do in this situation, or leave it like you've got it, it will still pull air out of the top of the case, just make sure you've got about an inch clearance from the top of the case, so the fan doesn't overheat from lack of air flow.
Details, Details, Its all in the Details, If you need help, Don't leave out the Details.
No. Your case is designed with the power supply upside down. I've seen this before, usually on cheap power supplies. You might be able to modify the case so the power supply is mounted correctly, but with the stock case it's upside down, and yes your case was designed that way, I don't know why.
<font color=blue>There are no stupid questions, only stupid people doling out faulty information based upon rumors, myths, and poor logic!</font color=blue>