HP ProLiant BL465c Gen8 Server Blade - Manual (Page 38)

Hardware options installation 38
is degrading. This allows DIMMs that have a higher probability of receiving an uncorrectable memory
error (which would result in system downtime) to be removed from operation.
Advanced Memory Protection options are configured in RBSU. If the requested AMP mode is not supported
by the installed DIMM configuration, the server blade boots in Advanced ECC mode. For more information,
see "HP ROM-Based Setup Utility (on page 57 )."
Maximum capacity
DIMM type DIMM rank One processor Two processors
RDIMM Single-rank 64 GB 128 GB
RDIMM Dual-rank 128 GB 256 GB
LRDIMM Quad-rank 256 GB 512 GB
For the latest memory configuration information, see the QuickSpecs on the HP website
( http://www.hp.com ).
Advanced ECC memory configuration
Advanced ECC memory is the default memory protection mode for this server blade. Standard ECC can
correct single-bit memory errors and detect multi-bit memory errors. When multi-bit errors are detected using
Standard ECC, the error is signaled to the server blade and causes the server blade to halt.
Advanced ECC protects the server blade against some multi-bit memory errors. Advanced ECC can correct
both single-bit memory errors and 4-bit memory errors if all failed bits are on the same DRAM device on the
DIMM.
Advanced ECC provides additional protection over Standard ECC because it is possible to correct certain
memory errors that would otherwise be uncorrected and result in a server blade failure. Using HP Advanced
Memory Error Detection technology, the server blade provides notification when a DIMM is degrading and
has a higher probability of uncorrectable memory error.
Online Spare memory configuration
Online spare memory provides protection against degraded DIMMs by reducing the likelihood of
uncorrected memory errors. This protection is available without any operating system support.
Online spare memory protection dedicates one rank of each memory channel for use as spare memory. The
remaining ranks are available for OS and application use. If correctable memory errors occur at a rate
higher than a specific threshold on any of the non-spare ranks, the server blade automatically copies the
memory contents of the degraded rank to the online spare rank. The server blade then deactivates the failing
rank and automatically switches over to the online spare rank.
General DIMM slot population guidelines
Observe the following guidelines for all AMP modes:
• Install DIMMs only if the corresponding processor is installed.
• When two processors are installed, balance the DIMMs across the two processors.
• White DIMM slots denote the first slot of a channel (Ch 1-A, Ch 2-C, Ch 3-B, Ch 4-D).
• Do not mix RDIMMs or LRDIMMs.