Installing A Memory Module - IBM System x3750 M4 Type 8722 Installation And Service Manual

Installing a memory module

The following notes describe the types of dual inline memory modules (DIMMs)
that the server supports and other information that you must consider when you
install DIMMs (see "System-board optional-device connectors" on page 31 for the
location of the DIMM connectors):
v Confirm that the server supports the DIMM that you are installing (see
v When you install or remove DIMMs, the server configuration information
v The server supports only industry-standard double-data-rate 3 (DDR3),
v The server supports 1.35-volt (low-voltage) registered DIMMs and 1.5-volt
http://www.ibm.com/systems/info/x86servers/serverproven/compat/us/).
changes. When you restart the server, the system displays a message that
indicates that the memory configuration has changed. You can use the Setup
utility to view the server configuration information, see "Using the Setup utility"
on page 127 for more information.
PC3-12800R 1600 MHz, PC3L-10600R-999 1333 MHz or PC3L-10600 1333 MHz
Load Reduced (LR), single-rank, dual-rank, or quad-rank, registered,
synchronous dynamic random-access memory (SDRAM) dual inline memory
modules (DIMMs) with error correcting code (ECC).
– The specifications of a DDR3 DIMM are on a label on the DIMM, in the
following format.
gGB eRxf-PC3-wwwwwm-a-b-c-d
where:
- gGB is the total capacity of the DIMM (for example, 1GB, 2GB, or 4GB)
- eR is the number of ranks
1R = single-rank
2R = dual-rank
4R = quad-rank
- xf is the device organization or bit width (for example, x4, x8, or x16)
4 = x4 organization (4 DQ lines per SDRAM)
8 = x8 organization
16 = x16 organization
- wwwww is the DIMM bandwidth, in MBps
6400 = 6.40 GBps (PC3-800 SDRAMs, 8-byte primary data bus)
8500 = 8.53 GBps (PC3-1066 SDRAMs, 8-byte primary data bus)
10600 = 10.66 GBps (PC3-1333 SDRAMs, 8-byte primary data bus)
12800 = 12.80 GBps PC3-1600 SDRAMs, 8-byte primary data bus)
- m is the DIMM type
E = Unbuffered DIMM (UDIMM) with ECC (x72-bit module data bus)
R = Registered DIMM (RDIMM)
U = Unbuffered DIMM with no ECC (x64-bit primary data bus)
- a is the CAS latency, in clocks at maximum operating frequency
- b is the JEDEC SPD Revision Encoding and Additions level
- c is the reference design file for the design of the DIMM
- d is the revision number of the reference design of the DIMM
(standard voltage) registered DIMMs as follows:
– Supported DIMMs with speeds of 1333 MHz or less support both 1.35 V and
1.5 V operation, depending on the configuration settings in the Setup utility.
Chapter 2. Installing optional devices
41