System BIOS Intel® 5000 Series Chipsets Server Board Family Datasheet
Revision 1.1
Intel order number D38960-004
38
For example: Correct configurations for Branch 0 are DIMM A1, DIMM A2. An incorrect
configuration for Branch 0 is DIMM A1. Because there is only one FBDIMM, none is available to
act as a spare.
The spare FBDIMMs do not contribute to available physical memory under normal system
operation. The Effective Memory field on the BIOS Setup utility screen will indicate this absence
of memory for the sparing operation.
Note: Memory sparing and mirroring features are currently disabled and will be made available
after production launch.
3.3.9.4 Memory Mirroring
Unlike memory sparing, the mirrored configuration is a redundant image of the memory, and
can continue to operate with some uncorrectable errors occur.
Memory mirroring is a RAS feature in which two identical images of memory data are
maintained, providing maximum redundancy. On the Intel
®
5000 MCH-based Intel server
boards, mirroring is achieved across Branch 0 and Branch 1 such that one of these branches is
the primary image and the other the secondary image. The memory controller always directs
read transactions to the primary branch. Write transactions are directed to both branches under
normal circumstances.
Because the available system memory is divided into a primary image and a copy of the image,
the effective system memory is reduced by one-half. For example, if the system is operating in
memory mirroring mode and the total size of the FBDIMMs is 1 GB, then the effective size of the
memory is 512 MB because half of the FBDIMMs are the secondary images.
For memory mirroring to work, participant FBDIMMs on the same DIMM sockets on the adjacent
branches must be identical in terms of technology, number of ranks, timing, and size.
The BIOS provides a setup option to enable memory mirroring. When memory mirroring is
enabled, the BIOS attempts to configure the memory system accordingly. If the FBDIMM
population is not suitable for mirroring, the BIOS disables mirroring and reverts to the default
non-RAS mode with maximum interleave, or to the single channel mode. The BIOS setup then
defaults to the eventual setting on the next boot.
See the server or workstation Technical Product Specification that applies to your product for
more information.
To Next Page
Loading...
Need help?
General
