HP Integrity rx7620 Server - User Service Guide, Sixth Edition

Figure 1-7 Memory Subsystem
PDH Riser Board
The Platform Dependant Hardware Riser board is a daughter card for the cell board. It contains
a micro-processor memory interface microcircuit, processor-dependent hardware including the
processor-dependent code (PDC), flash memory, and a manageability microcontroller, called
the Platform Dependant Hardware Controller (PDHC) with associated circuitry. The PDH obtains
cell board configuration information from cell board signals and from the cell's LPM.
The PDH riser board contains circuitry that the cell board requires to function and, therefore,
each cell board must have a PDH Riser installed before it is added to a server.
Central Processor Units
The cell board can hold up to four CPU modules and can be populated with CPUs 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 1-2. For the locations on the cell board for installing
CPUs, see Figure 1-8. A single CPU configuration is not available for the cell board.
Table 1-2 Cell Board CPU Load Order
Socket 3 LocationSocket 2 LocationSocket 1 LocationSocket 0 LocationNumber of
CPUs Installed
EmptyTerminatorEmpty slotCPU installedTwo
EmptyCPU installedEmpty slotCPU installedFour
Empty or CPUCPU installedCPU or emptyCPU installedSix
CPU installedCPU installedCPU installedCPU installedEight
Detailed HP Integrity rx7620 Server Description 23