The heat pipes of the Fourier IV are bent more than those of the Fourier III. As a result, the copper heatsink has a negative slope angle relative to the mainboard while the aluminum one is parallel to the mainboard surface.

There is a thickening in the base of each cooler under the middle pipes, just like in the VertiCool IV:

A distinguishing feature of the Fourier coolers is that the 120mm fan of model III has a constant speed of 1500rpm while the speed of the 92mm fan of the Fourier IV can be varied from 2000 to 3500rpm using the speed controller. The latter is a copy of the one included with the VertiCool IV.

The base of each cooler is finished equally well: its quality somewhere in between the DiamondCool and the VertiCool IV.

You?ll need a metal back-plate to install the cooler on any of the supported platforms. You have to take the mainboard out of the system case to do that but the first thing you should do is to secure an appropriate fastener on the cooler?s base:

LGA775

Socket 754/939/940

Socket AM2