Using The Memory Ras Features - NEC Express5800 User Manual

Using the Memory RAS Features

The server has RAS feature including "Standard memory configuration (x4 SDDC ECC memory),
"Memory sparing feature", "Memory mirroring feature", and "memory LockStep (x8 SDDC ECC
memory) feature. SDDC (Single Device Correction) allows automatic correction of memory error
(multi-bit error).
IMPORTANT:
To use the memory mirroring and memory LockStep features, you

need to install the additional DIMMs of the following models:
N8102-392/393/394/395/396.
To use memory RAS feature, additional 2GB/4GB/8GB/16GB

memory board is required. The 1GB DIMMs and additional 1GB
memory board is unavailable for memory RAS feature.
"Memory mirroring feature" and "memory LockStep (x8 SDDC

ECC memory) feature cannot be used in the standard memory
configuration.
The memory area on the motherboard of the server is divided into two memory channels as shown
in the figure below.
The memory mirroring and memory LockStep features keep memory redundancy between memory
channels by monitoring or altering memory active/inactive status, respectively.
Upgrading Your Server 9-87