Cell Board; Figure 1-6 Cell Board - HP Integrity rx7620 Installation Manual

Introduction
Detailed HP Integrity rx7620 Server Description

Cell Board

The cell board contains several hardware blocks connected by several data buses. The major hardware blocks
are the Central Processor Units (CPUs), the Cache Coherency Controller (CC), the memory Controllers, and
the Memory. Minor hardware blocks include Clock Distribution, Power Distribution, Reset Circuit, and PDH
Riser Board Interface. The buses include two Front Side Buses (FBS0 and FBS1), a Memory (MID) bus, a
Crossbar (XB) bus, and an I/O bus. All these blocks come together at the CC chip.
Figure 1-6 Cell Board
The HP Integrity rx7620 Server has a 48V distributed power system and receives the 48V 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.
Because of space limitations on the cell board, the PDH/PDHC circuitry resides on a riser board that plugs
into the cell board at a right angle. The cell board also includes clock circuits, test circuits, and de-coupling
capacitors.
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Chapter 1