HP ProLiant Intel-based 100-series G6 servers

will provide more significant power savings than the LP DIMM. The LP DIMM continues to be

available for Intel-based G6 servers.

See the server QuickSpecs for DIMM kits available for each platform.

DIMM configuration guidelines

Administ

rators can configure ProLiant 100-series G6 servers using either RDIMMs or UDIMMs but

RDIMM and UDIMM memory cannot be mixed within a single server. ProLiant 100-series G6 servers

have up to 18 DIMM slots, allowing larger memory capacities than with platforms that used DDR-2.

ProLiant G6 servers optimize memory performance by operating DDR3 memory at the maximum rate

possible based on the memory configuration and the processor that is installed.

When choosing memory configurations for ProLiant 100-series G6 systems, the following guidelines

should prove helpful:

 UDIMM configurations are limited to a maximum of two UDIMMs per memory channel because the

memory controller must drive the address and command signals to each DRAM chip on a channel.

This results in a 48 GB maximum configuration in ProLiant 100-series G6 servers. Because they

require fewer components, UDIMMs are typically less expensive than RDIMMs.

 RDIMM configurations can provide larger memory capacity configurations because the memory

controller only drives the address and command signals to a single register chip, thereby reducing

the electrical load on the memory controller. Users requiring large memory footprints can install

Quad-Rank RDIMMs for a total of 192 GB.

 For smaller memory configurations, installing only one or two DIMMs per memory channel can

potentially increase memory performance. In many instances this allows administrators to clock the

memory channel at a higher data rate.

 Quad-rank DIMMs support up to 2 DIMMs per channel

 Low voltage DIMMs can provide up to 10% DIMM power savings. Low- and standard-voltage

DIMMS are compatible; systems automatically adjust voltage based on DIMMs installed.

 Processor SKU determines the ability of ProLiant G6 servers to run DDR3 memory at a top speed of

1333 MT/s. The processor SKU also dictates the range of speeds possible in different DIMM per

channel (DPC) configurations. DIMM operating speeds are also subject to memory slot

configuration and number of memory slots (12, 16, or 18). Only HP branded DIMMS have been

fully validated to operate at 1333 MT/s data rates with two DIMMs per channel. Therefore, HP

does not recommend this configuration when using third-party DIMMs because they may not meet

HP’s stringent design requirements.

NOTE:

DDR3 DIMM speeds will vary depending on number of DIMMs per channel. Consult

the server QuickSpec to determine DIMM speeds for given configurations.

For help configuring DDR3 memory in ProLiant G6 servers, use the DDR3 Memory Configuration Tool

found at http://

www.hp.com/go/ddr3memory-configurator.

Memory Mirroring with DDR3

ProLiant 1

00-series G6 servers using the Xeon 5500 and 5600 processors are designed to use

memory mirroring which protects the system against uncorrectable memory errors that would

otherwise result in a system hang or crash. Mirroring occurs when all data is written to both sets of

physical memory in channels one and two. Administrators can configure memory mirroring through

BSU. To implement mirroring with DDR3, the two memory channels must be populated identically. The

third memory channel must be empty.