HP Integrity rx8620 Server User Service Guide

Figure 1-6 Memory Subsystem
PDH Riser Board
The HP Integrity rx8620 Server PDH riser board is a small card that plugs into the cell board at
a right angle. The PDH riser interface contains a microprocessor memory interface microcircuit,
hardware including the processor dependant code (PDC) flash memory, and a manageability
microcontroller with associated circuitry. The PDH obtains cell board configuration information
from cell board signals and from the cell board local power module (LPM).
Central Processor Units
The cell board can hold up to four CPU modules and can be populated with modules in increments
of one after meeting the minimum of two CPUs installed on the cell board. On a cell board, the
processors must be the same type and speed. For the CPU load order that must be maintained
when adding CPUs to the cell board, see Table 1-1. For the locations on the cell board for installing
CPUs, seeFigure 1-7. A single CPU configuration is not available for the cell board.
NOTE: When installing dual-core CPUs, if only one CPU module is installed on the cell board,
a terminator must be installed in CPU socket 2.
Table 1-1 Cell Board CPU Load Order
CPU 0 LocationCPU 1 LocationCPU 3 LocationCPU 2 LocationNumber of
CPUs Installed
CPU installedEmpty slotEmpty slotTerminatorTwo
CPU installedEmpty slotEmpty slotCPU installedFour
CPU installedCPU installedEmpty slotCPU installedSix
CPU installedCPU installedCPU installedCPU installedEight
22 Overview