Owners Manual

NOTE: MT/s indicates DIMM speed in MegaTransfers per second.
The system supports Flexible Memory Configuration, enabling the system to be configured and run in any valid chipset
architectural configuration. The following are the recommended guidelines for installing memory modules:
● All DIMMs must be DDR4.
● x4 and x8 DRAM based memory modules can be mixed.
● Up to two RDIMMs can be populated per channel regardless of rank count.
● A maximum of two different ranked DIMMs can be populated in a channel regardless of rank count.
● If memory modules with different speeds are installed, they will operate at the speed of the slowest installed memory
module(s).
● Populate memory module sockets only if a processor is installed.
○ For single-processor systems, sockets A1 to A12 are available.
○ For dual-processor systems, sockets A1 to A12 and sockets B1 to B12 are available.
● Populate all the sockets with white release tabs first, followed by the black release tabs.
● When mixing memory modules with different capacities, populate the sockets with memory modules with the highest
capacity first.
For example, if you want to mix 8 GB and 16 GB memory modules, populate 16 GB memory modules in the sockets with white
release tabs and 8 GB memory modules in the sockets with black release tabs.
● Memory modules of different capacities can be mixed provided other memory population rules are followed.
For example, 8 GB and 16 GB memory modules can be mixed.
● In a dual-processor configuration, the memory configuration for each processor must be identical.
For example, if you populate socket A1 for processor 1, then populate socket B1 for processor 2, and so on.
● Mixing of more than two memory module capacities in a system is not supported.
● Unbalanced memory configurations will result in a performance loss so always populate memory channels identically with
identical DIMMs for best performance.
● Populate six identical memory modules per processor (one DIMM per channel) at a time to maximize performance.
DIMM population update for Performance Optimized mode with quantity of 4 and 8 DIMMs per processor.
● When the DIMM quantity is 4, the population is slot 1, 2, 4, 5.
● When the DIMM quantity is 8, the population is slot 1, 2, 4, 5, 7, 8, 10, 11.
Mode-specific guidelines
The configurations allowed depend on the memory mode selected in the System BIOS.
Table 9. Memory operating modes
Memory Operating Mode Description
Optimizer Mode The Optimizer Mode if enabled, the DRAM controllers
operate independently in the 64-bit mode and provide
optimized memory performance.
Mirror Mode The Mirror Mode if enabled, the system maintains two
identical copies of data in memory, and the total available
system memory is one half of the total installed physical
memory. Half of the installed memory is used to mirror the
active memory modules. This feature provides maximum
reliability and enables the system to continue running even
during a catastrophic memory failure by switching over to the
mirrored copy. The installation guidelines to enable Mirror
Mode require that the memory modules be identical in size,
speed, and technology, and they must be populated in sets of
6 per processor.
Single Rank Spare Mode Single Rank Spare Mode allocates one rank per channel as a
spare. If excessive correctable errors occur in a rank or
channel, while the operating system is running, they are
68 Installing and removing system components