IBM eServer Cluster 1600 Managed by PSSP 3.5: What's New

Chapter 2. New hardware 33

For further expansion up to eight 4U height 7311-D10 I/O drawers with six

additional hot plug PCI-X bus slots can be added to increase the number of

PCI-X slots to 55.

2.4.2 CPU board layout

The POWER4 microprocessor in this machine is packed on CPU cards in a

SCM. All other pSeries (except the p630) have so called multi-chip modules

(MCM), where four POWER4 processors are packed on one module. One SCM

is mounted on a CPU board, in addition to 8 MB of Level 3 cache with the 1.2

GHz processor or 32 MB of Level 3 cache with the 1.45 GHz processor. Up to 16

GB double data rate (DDR) memory can be installed per card. The theoretical

bandwidth to the local memory on the card is 6.4 GB/s, using four channels. Four

processor cards can be included in the p650, where all cards must have the

same frequency and the same amount of memory for optimal parallel work

balancing. A simplified illustration of one processor card is shown in Figure 2-11.

Figure 2-11 Simplified layout of a p650 processor card

L1 Data L1 Inst.

CPU Core

1.2 / 1.45

GHz

L1 Data L1 Inst.

CPU Core

1.2 / 1.45

GHz

Shared L2 Cache 1.5 MB

L3 Directory

DIMM

DIMM

DIMM

DIMM

DIMM

DIMM

DIMM

DIMM

Memory

Controller

L3 Cache 8/32 MB

SMILSMIL

SMIL

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