On the surface, installing the PC AirCon into a PC enclosure seems to be very straight forward and quite easy. But you will quickly see that once installed, the PAC 400 completely blocks access to the bay above and the bay below the main unit.
Because of this you might initially think that installing the PC AirCon in the top drive bay would minimize the loss of available bays, but it also brings up a less obvious problem—the installed position can have a big effect on case cooling performance!
Installing the PC AirCon in the top drive bay as shown above resulted in virtually no cooling effect inside the case because the power supply was sucking in the cool air and exhausting it out the back of the case. This is good for the power supply but negated any cooling effect for other critical components (CPU, GPU, RAM, etc).
Installing the PC AirCon in the lowest position possible (without blocking the 3-1/2′ bays) may produce a better cooling effect by blowing cool air directly onto the components that need it most. Maximum cooling can be obtained by directly ducting the cool air onto specific components.