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.

2.1.2Memory 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.

2.1.3I/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.

2-2SPARC Enterprise M8000/M9000 Servers Overview Guide • April 2007