Table 7. Memory-card installation sequence for memory-mirroring configuration (continued)DIMM pair installationorder Memory card Connector numbersThird 1 2 and 62 2 and 6Fourth 3 2 and 64 2 and 6Fifth 1 3 and 72 3 and 7Sixth 3 3 and 74 3 and 7Seventh 1 4 and 82 4 and 8Eighth 3 4 and 84 4 and 8v There are four memory power buses, which are split among the four memorycards.v For memory mirroring, you must install DIMMs in sets of four, one pair in eachmemory card. All DIMMs in each set must be the same size and type. Memorycards 1 and 2 mirror each other, and memory cards 3 and 4 mirror each other.v If a problem with a DIMM is detected, light path diagnostics will light thesystem-error LED on the front of the server, indicating that there is a problemand guiding you to the defective DIMM. When this occurs, first identify thedefective DIMM; then, remove and replace the DIMM.The following illustration shows the LEDs that are visible on top of the memorycard.42 IBM System x3850 M2 and System x3950 M2 Types 7141 and 7233: User’s Guide
