Heathrow also provides power-management control functions for energy saving features included on Power Macintosh computers. The Heathrow IC is connected to the PCI bus and uses the 30–33 MHz PCI bus clock. | Heathrow also provides power-management control functions for energy saving features included on Power Macintosh computers. The Heathrow IC is connected to the PCI bus and uses the 30–33 MHz PCI bus clock. |