Sun X4100 0915ALEB30-HD 0915ALEB30 User Manual

Product codes

0915ALEB30

Sun Microsystems, Inc.

Figure 2-2: Dual-Core AMD Opteron Processor Architecture

Note: Sun Fire X4100 M2 and X4200 M2 servers support both Standard Edition (95W) and Special Edition (120W) of the Next Genera-
tion AMD Opteron processor.

Processor VRM

Each processor receives core voltage input from an individual voltage regulator module (VRM). The VRMs regulate the system cur-

rent and voltage according to the VID code output by the CPU package. The VRM is a DC-to-DC point of load convertor specified for

+12 Volt input and programmable 100 Amp output.

Memory Architecture

Each CPU includes a low-latency, high-bandwidth, integrated DDR2 memory controller that reduces latencies during memory access

over traditional front-side bus-based memory controllers. Up to four ECC Registered DDR2-667 memory modules per CPU are sup-

ported. The AMD Opteron processor's memory controller works in 64-bit (single channel) or 128-bit (dual channel) mode ECC opera-

tion. For best performance results, it is recommended to run 128-bit ECC operation mode. To run in 128-bit mode, DIMMs should be

populated so that there is at least one DIMM in each 64-bit channel of each processor. The controller supports 1 bit per byte ECC, and

supports DDR2-667 (PC2-5300) registered DDR SDRAM modules.

The Sun Fire X4100 M2 and X4200 M2 servers have 4 DDR2 DIMM slots per CPU that are color-coded white and black to indicate popu-

lation order (white = 0,1 and black = 2,3; white pair first). LED fault indicators controlled by the ILOM Service Processor provide the

ability to easily identify failed DIMM modules. Memory capacity scales with the number of processors. Therefore, memory attached

to an unpopulated processor slot is unaddressable. As a result, a single processor machine can support a maximum of four DIMMs or

16 GB (4 x 4 GB) of memory. A dual CPU server supports a maximum of eight DIMMS or 32 GB (8 x 4 GB) of memory.

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