Intake VS. Exhaust Heatsink Fan Orientation

[Operandi]

In most scenarios having the fan act as an intake (facing down towards the CPU) will give you better performance. There are exceptions to this, Alpha's always performed better with the fan exhausting heat due to their use of the fan shroud.

Anyway?..I just stumbled across this XP-120 review; here the CPU temps are the same either way but system temps drop with the fan used in the exhaust position. I'm guessing the reason for this the pressure behind the fan is slow at such slow RPM's that it really doesn?t matter which way the fan faces, this might be the case with when any low pressure fan is used?

 

[Operandi]

bump,

I also found a review of alpha using a ultra fast hence high pressure 80mm fan performing better with fan blowing towards the board. Opposite of how it should be used but it would hold up that my theory that it doesn?t matter which way the fan faces in low pressure situations.