Hardware Overview 27
parity-checked synchronous L2 cache. The Model 150 also features an enhanced memory controller that uses ECC SDRAM memory. The local system bus on the RS/6000 Model 150 is a 60X bus running at 83 MHz. This bus is 64 bits wide (with an additional 8 bits for parity) and is synchronous. The processor clock and regulator card reside as one unit, namely the OVdd/Vdd/PLL card. This is illustrated in the planar design of the Model 150 in Figure 8.
Figure 8. Planar Block Diagram of the RS/6000 Model 150
In the Model 150, the 60X bus runs from the PowerPC 604e processor and connects to an enhanced memory controller chip, which has a processor
Integrated 1 MB
Parity L2 Cache
IPGA
604e-375 MHz
OVdd/Vdd/PLL
IBM
Card
Ctrl/Buffer
ECC
PCIB/MC
ECC SDRAM
DIMM
100/10
Ethernet
Ultra SCSI
Enet RJ45
Enet AUI
Local bus 83 MHz
Int Ultra SCSI
Repeater
Ext Ultra SCSI
RISER
PCI/PCI
Bridge &
Clock
Drivers
Tablet
Parallel
Serial 1
Serial 2
Floppy
Keyboard
Mouse
National
PC87308
National
Secondary
Business
Audio
IBM MPIC
Controller
Headphone
Speaker
Line Out
Line In
Microphone
1 MB
Flash
ROM
32 KB
NVRAM Logic Front Panel
Controller Enhanced
Security Power
Mgmt
PCI Bus 33 MHz ISA Bus 8 MHz
PCI-to-ISA
Bridge
Unit
UART 16550
PCI Bridge
PCI Slot 1
PCI Slot 4
PCI Slot 5
PCI Slot 2
PCI Slot 3