Abstract: A blower having counter rotating fan blades for generating uniform air flow across a heat sink, which maximizes the cooling efficiency of the heat sink. The counter rotating fan blades may individually controlled to optimize performance of the blower. Only one set of fan blades may be used for low temperature conditions, thereby consuming less power and reducing acoustic noise, while both sets of fan blades may be used for high temperature conditions, thereby maximizing heat transfer. The blower may be configured to operate one or both sets of fan blades at a desired operating fan speed based on one or more pre-determined conditions. The pre-determined conditions include at least one of temperature, acoustic, and power levels and or measurements of one or more components of the computer system.