IBM System x3400 M3
13
Memory options
IBM DDR3 memory is compatibility tested and tuned for optimal System x performance and throughput.
IBM memory specifications are integrated into the light path diagnostics for immediate system
performance feedback and optimum system uptime. From a service and support standpoint, IBM memory
automatically assumes the IBM system warranty, and IBM provides service and support worldwide.
The IBM System x3400 M3 supports DDR3 memory. The server supports up to eight DIMMs when one
processor is installed and up to 16 DIMMs when two processors are installed. However, the maximum
number of DIMMs is limited by the number of ranks in the DIMMs:
RDIMMs
Up to 16 single-rank RDIMMs for a maximum of 64 GB (16x 4 GB)
Up to 16 dual-rank RDIMMs for a maximum of 128 GB (16x 8 GB)
UDIMMs
Up to 16 single-rank UDIMMs for a maximum of 16 GB (16x 1 GB)
Up to 16 dual-rank UDIMMs for a maximum of 64 GB (16x 4 GB)
Each CPU has three memory channels, two of which contain three DIMMs per channel and the third
contains two DIMMs. RDIMMs can be populated up to three per channel. However, UDIMMs can only be
populated two DIMMs per channel. That is, you can have up to 16 RDIMMs installed in the server, but
only up to 12 UDIMMs. Mixing UDIMMs and RDIMMs is not supported.
Maximum memory speed is limited by memory speed supported by the specific CPU (that is, if the CPU
only supports 1066 MHz, then the memory speed cannot exceed 1066 MHz in any case) and by the
number and type of DIMMs installed (whatever is lower), as follows:
Intel Xeon 5600 series processors:
1333 MHz when one or two single-rank or dual-rank RDIMMs per channel are installed or one
UDIMM per channel is installed
1066 MHz when two UDIMMs per channel are installed
800 MHz when three single-rank or dual-rank RDIMMs per channel are installed
Quad-core Intel Xeon 5500 series processors:
1333 MHz when one single-rank or dual-rank RDIMM per channel is installed or one UDIMM per
channel is installed
1066 MHz when two single-rank or dual-rank RDIMMs per channel are installed, or two UDIMMs
per channel are installed
800 MHz when three single-rank or dual-rank RDIMMs per channel are installed
Dual-core Intel Xeon 5500 series processors only support memory speed at 800 MHz.
The server supports both 1.5 V and 1.35 V DIMMs. Mixing 1.5 V and 1.35 V DIMMs in the same server is
supported for Intel Xeon 5600 series processor-based systems. In such a case, all DIMMs operate at 1.5
V. Intel Xeon 5500 series processor-based systems do not support 1.35 V DIMMs.
The following memory protection technologies are supported:
ECC
ChipKill (for x4-based RDIMMs)
Memory mirroring
Memory sparing
