2-2 SPARC Enterprise M8000/M9000 Servers Overview Guide • April 2007
The SPARC Enterprise M8000 server, SPARC Enterprise M9000 server, and the
SPARC Enterprise M9000 server with expansion cabinet take advantage of system
scalability by supporting up to 16, 32, or up to 64 CPU modules, respectively.
CPU modules running at different clock frequencies can be used in a single system.
The latest CPUs can therefore be installed when improved processing performance is
required.
2.1.2 Memory Subsystem
The memory subsystem controls memory access and cache memory. The server uses
DDR-II DIMM memory.
Each CMU has thirty-two memory slots.
Also, the SPARC Enterprise M8000 server, SPARC Enterprise M9000 server, and
SPARC Enterprise M9000 server with expansion cabinet can mount up to 128, 256, or
512 DIMMs, respectively.
The memory subsystems use up to eight-way interleaving, providing higher-speed
memory access.
Memory mirror mode is supported for every pair of memory buses in a CMU. This
enables continued operation using the other non-defective bus if an error occurs in
one bus. Memory mirror mode can be set up by the system administrator.
2.1.3 I/O Subsystem
The I/O subsystem controls data transfer between the main unit and I/O devices.
These servers use PCIe as the interconnect bus for I/O devices.
Each IOU contains eight-lane (x8) PCIe slots. Also, eight-lane PCIe slots or 133-MHz
64-bit PCI-X slots can be in a mounted through an External I/O Expansion Unit.
The SPARC Enterprise M8000 server, SPARC Enterprise M9000 server, and the
SPARC Enterprise M9000 with expansion cabinet can mount up to 32, 64, or 128
PCIe-compatible cards, respectively.
PCI-Express slots or PCI-X slots can be added by mounting an External I/O
Expansion Unit through a PCI-Express slot.
