IBM P5 570 manual Processor drawer interconnect cables

Figure 2-5 Processor card with DDR1 memory socket layout view

There are two system backplanes in the p5-570 system. A GX+ bus planar, which docks vertically into the system planar, is always present in the system. The processor cards dock directly into this backplane from the front. A horizontal backplane exists below the CPU cards that is co-planar with the I/O backplane. This backplane routes the vertical fabric bus between the processor cards. This backplane is also used for power distribution from the CPU regulators that are housed next to the processor cards. (See Figure 1-1 on page 4.)

2.2.1 Processor drawer interconnect cables

In combined systems that are made of more than one p5-570 building block, the connection between processor cards in different building blocks is provided with a processor drawer interconnect cable. Different processor drawer interconnect cables are required for the different numbers of p5-570 building blocks that a combined system can be made of, as shown in Figure 2-6.

Because of the redundancy and fault recovery built-in to the system interconnects, a drawer failure does not represent a system failure. Once a problem is isolated and repaired, a system reboot may be required to reestablish full bus speed, if the failure was specific to the interconnects.

The SMP fabric bus that connects the processors of separate p5-570 building blocks is routed on the interconnect cable that is routed external to the building blocks. The flexible cable attaches directly to the processor cards, at the front of the p5-570 building block, and is routed behind the front covers (bezels) of the p5-570 building blocks. There is an optimized cable for each drawer configuration. The Figure 2-6illustrates the logical fabric bus connections between the drawers, and shows the additional space required left of the bezels for rack installation.

24p5-570 Technical Overview and Introduction