• Memory Mode (default): The module operates as 100% memory module. Data is volatile and DRAM
acts as a cache for DCPMMs. This is the factory default mode.
• App Direct Mode: The module operates as a solid-state disk storage device. Data is saved and is
non-volatile.
• Mixed Mode (25% Memory Mode + 75% App Direct): The module operates with 25% capacity used as
volatile memory and 75% capacity used as non-volatile storage.
Intel Optane DC Persistent Memory Module Population Rules and Performance Guidelines
This topic describes the rules and guidelines for maximum memory performance when using Intel Optane
DC persistent memory modules (DCPMMs) with DDR4 DIMMs.
DIMM Slot Numbering
The following figure shows the numbering of the DIMM slots on the CPU module board. When a CPU module
is in bay 1 (the lower bay), the system numbers the CPUs as CPU 1 and CPU 2. When a CPU module is in
bay 2 (the upper bay), the system numbers the CPUs as CPU 3 and CPU 4.
Figure 44: DIMM Slot Numbering
Configuration Rules
Observe the following rules and guidelines:
• To use DCPMMs in this server, four CPUs must be installed.
• Intel Optane DC persistent memory modules require Second Generation Intel Xeon Scalable processors.
You must upgrade the server firmware and BIOS to version 4.0(4) or later and then install the supported
Second Generation Intel Xeon Scalable processors before installing DCPMMs.
• When using DCPMMs in a server:
• The DDR4 DIMMs installed in the server must all be the same size.
• The DCPMMs installed in the server must all be the same size and must have the same SKU.
• The DCPMMs run at 2666 MHz. If you have 2933 MHz RDIMMs or LRDIMMs in the server and you
add DCPMMs, the main memory speed clocks down to 2666 MHz to match the speed of the DCPMMs.
• Each DCPMM draws 18 W sustained, with a 20 W peak.
• The following table shows supported DCPMM configurations for this server. Fill the DIMM slots for
CPU 1 and CPU 2 in CPU module 1 as shown, depending on which DCPMM:DRAM ratio you want to
populate. If CPU module 2 is present, fill the DIMM slots for CPU 3 and CPU 4 as shown.
Maintaining the Server
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Maintaining the Server
Intel Optane DC Persistent Memory Module Population Rules and Performance Guidelines