Starting at the top level bus and working downward in the bus hierarchy, at the top level is the CPU bus with a Hammerhead controller (Apple Part # 343S1190) which is also found on the PM9500. The CPU, as mentioned, is a PowerPC 604 or 604e. The CPU bus-to-PCI bus bridges are Bandit controllers (343S0020). Both the ANS and the PM9500 have two Bandit controllers and two separate PCI busses. All devices at the CPU bus level are identical between the ANS and PM9500. On both systems the CPU Bus Clock is supplied by the removable CPU card. However, on the ANS the clock buffer which splits the System Clock for all the CPU Bus Devices is on the logic board, whereas on the PowerMac 9500 the clock buffer is on the CPU card.