Sun Microsystems X4600, X4600 M2 Memory is populated in pairs, CPU and integrated Heatsink, Order of installation

Sun Microsystems, Inc.
populated in pairs in memory slots from the top of the board toward the processor heat sink at bottom of the
board. Memory slots should be populated with D7 and D6 first, then D5 and D4, then D3 and D2, and finally D1
and D0 next to the processor heat sink. 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, so
memory attached to an unpopulated processor slot is unaddressable. As a result, a dual-socket machine can
support a maximum of sixteen DIMMs.
A fully populated, eight-CPU server supports a maximum of 64 DIMMS or 256 GB of memory. With just two or
four DIMMs populated, the system runs memory at 667 MHz. With 6 or 8 DIMMs populated, the system runs
memory at 533 MHz. The white group (D7-D4) of 4 DIMMs must have the same size DIMMs (1GB, 2GB, or
4GB). The black (D3-D0) group of DIMM slots must have the same size DIMMs but can be a different size
DIMMs than the white group of DIMMS.
Figure 2-7: 8 DIMM Processor Board with Memory Installation Order
Other features of the Sun Fire X4600 and Sun Fire X4600 M2 servers memory architecture include:
•Dedicated on-die 128-bit wide DDR memory controller
•Memory bandwidth up to 6.4 GB/sec. @ DDR400 (Sun Fire X4600)
•Memory bandwidth up to 10.7 GB/sec. @ DDR2/667 (Sun Fire X4600 M2)
•Under 80 ns latency
•Registered ECC DDR400 (PC3200) supported (Sun Fire X4600)
•Registered ECC DDR2/667 (PC2-5300) supported (Sun Fire X4600 M2)
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Memory is populated in pairs
CPU and
integrated
Heatsink
Order of
installation
DIMM Slots
1: D7, D6
2: D5, D4
3: D3, D2
4: D1, D0