Dimms - Sun Microsystems Sun Fire V445 Server Administration Manual

Note – CPU/Memory modules on a Sun Fire V445 server are not hot-pluggable or
hot-swappable.
The UltraSPARC IIIi processor is a high-performance, highly integrated superscalar
processor implementing the SPARC V9 64-bit architecture. The UltraSPARC IIIi
processor can support both 2D and 3D graphics, as well as image processing, video
compression and decompression, and video effects through the sophisticated Visual
Instruction Set extension (Sun VIS software). The VIS software provides high levels
of multimedia performance, including two streams of MPEG-2 decompression at full
broadcast quality with no additional hardware support.
The Sun Fire V445 server employs a shared-memory multiprocessor architecture
with all processors sharing the same physical address space. The system processors,
main memory, and I/O subsystem communicate via a high-speed system
interconnect bus. In a system configured with multiple CPU/Memory modules, all
main memory is accessible from any processor over the system bus. The main
memory is logically shared by all processors and I/O devices in the system.
However, memory is controlled and allocated by the CPU on its host module, that is,
the DIMMs on CPU/Memory module 0 are managed by CPU 0.

DIMMs

The Sun Fire V445 server uses 2.5-volt, high-capacity double data rate dual inline
memory modules (DDR DIMMs) with error-correcting code (ECC). The system
supports DIMMs with 512-Mbyte, 1-Gbyte, and 2-Gbyte capacities. Each
CPU/Memory module contains slots for four DIMMs. Total system memory ranges
from a minimum of 1 Gbyte (one CPU/Memory module with two 512-Mbyte
DIMMs) to a maximum of 32 Gbytes (four modules fully populated with 2-Gbyte
DIMMs).
Within each CPU/Memory module, the four DIMM slots are organized into groups
of two. The system reads from, or writes to, both DIMMs in a group simultaneously.
DIMMs, therefore, must be added in pairs. The figure below shows the DIMM slots
and DIMM groups on a Sun Fire V445 server CPU/Memory module. Adjacent slots
belong to the same DIMM group. The two groups are designated 0 and 1 as shown
in .
FIGURE 4-1
74 Sun Fire V445 Server Administration Guide • September 2007