OK, so what I can understand is that the Revo works by having a mix of coolant in the 'cooling-loop'. Part of the coolant is liquid and part of it is a liquid that expands to a gas under the heat of the CPU (and cools back to a liquid when it passes through the radiator). There is a mini reservoir in the base of the cooler, and as the coolant gets hot it moves up the big pipe, and the resulting convection system moves it all around the cooler. The coolant that changes to gas creates bubbles in this loop and these help move the liquid round (somehow).



Link: Xtremecomputing