Sun Microsystems X4240, X4440, X4140 manual Troubleshooting DIMM Problems, DIMM Population Rules

C H A P T E R 3

Troubleshooting DIMM Problems

This chapter describes how to detect and correct problems with the server’s Dual Inline Memory Modules (DIMM)s. It includes the following sections:

■“DIMM Population Rules” on page 11

■“DIMM Replacement Policy” on page 12

■“How DIMM Errors Are Handled by the System” on page 12

■“Isolating and Correcting DIMM ECC Errors” on page 18

DIMM Population Rules

The DIMM population rules for the server are as follows:

■Each CPU can support a maximum of eight DIMMs.

■The DIMM slots are paired and the DIMMs must be installed in pairs (0-1, 2-3, 4- 5, and 6-7). See FIGURE 3-1and FIGURE 3-2. The memory sockets are colored black or white to indicate which slots are paired by matching colors.

■DIMMs are populated starting from the outside (away from the CPU) and working toward the inside.

■CPUs with only a single pair of DIMMs must have those DIMMs installed in that CPU’s outside white DIMM slots (6 and 7). See FIGURE 3-1and FIGURE 3-2.

■Only DDR2 800 Mhz, 667Mhz, and 533Mhz DIMMs are supported.

■Each pair of DIMMs must be identical (same manufacturer, size, and speed).

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