HP ProLiant SL4540 Gen8 Server - Manual (Page 35)

Hardware options installation 35
Memory subsystem architecture
The memory subsystem in this node is divided into channels. Each processor supports three channels, and
each channel supports two DIMM slots, as shown in the following table.
DIMM slots in this server are identified by number and by letter. Letters identify the population order. Slot
numbers indicate the DIMM slot ID for spare replacement.
Channel Slot designation Slot number
1 A
D 1
2
2 B
E
3
4
3
C
F
5
6
This multichannel architecture provides enhanced performance in advanced ECC mode. For the location of
the slot numbers, see "DIMM slots (on page
9 )."
Single-rank and dual-rank DIMMs
DIMM configuration requirements are based on these classifications:
• Single-rank DIMM—One set of memory chips that is accessed while writing to or reading from the
memory.
• Dual-rank DIMM—Two single-rank DIMMs on the same module, with only one rank accessible at a time.
The server memory control subsystem selects the proper rank within the DIMM when writing to or reading
from the DIMM.
Dual-rank DIMMs provide the greatest capacity with the existing memory technology. For example, if current
DRAM technology supports 2-GB single-rank DIMMs, a dual-rank DIMM would be 4 GB.