Chapter 1
HP Integrity rx8640 and HP 9000 rp8440 Server Overview
Detailed Server Description
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Cell Board
The cell board, illustrated in Figure 1-6, contains the processors, main memory, and the CC application
specific integrated circuit (ASIC) which interfaces the processors and memory with the I/O. The CC is the
heart of the cell board, providing a crossbar connection that enables communication with other cell boards in
the system. It connects to the processor dependent hardware (PDH) and microcontroller hardware. Each cell
board holds up to four processor modules and 16 memory DIMMs. One to four cell boards can be installed in
the server. A cell board can be selectively powered off for adding processors, memory or maintenance of the
cell board, without affecting cells in other configured partitions.
Figure 1-6
Cell Board
The server has a 48 V distributed power system and receives the 48 V power from the system backplane
board. The cell board contains DC-to-DC converters to generate the required voltage rails. The DC-to-DC
converters on the cell board do not provide N+1 redundancy.
The cell board contains the following major buses:
•
Front side buses (FSB) for each of the four processors
•
Four memory buses (one going to each memory quad)
•
Incoming and outgoing I/O bus that goes off board to an SBA chip
•
Incoming and outgoing crossbar busses that communicate to the crossbar chips on the system backplane
•
PDH bus that goes to the PDH and microcontroller circuitry
All of these buses come together at the CC chip.
Summary of Contents for Integrity rx8640
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