Memory Overview - Intel SRPL8 Product Manual

Memory Overview

Main memory resides on two add-in boards, called memory modules. Each memory module
contains slots for 16 DIMMs and is attached to the profusion carrier through a 300-pin connector
on the midplane. The memory controller supports PC 100-registered SDRAM DIMMs. Various
DIMM sizes are supported, but each DIMM must be at least 128 MB. Memory amounts from
128 MB to 16 GB per module are supported. The ECC used for the memory module is capable of
correcting single-bit errors (SBEs) and detecting 100% of double-bit errors over one code word.
Nibble error detection is also provided.
You can install:
From 1 to 32 DIMMs (total number of DIMMs for two memory modules)
Equal number of DIMMs on each memory module (except when only one DIMM is used)
NOTE
When only a single memory module is installed, DIMM sizes on that
module may vary, but when both memory modules are installed, the DIMM
configuration on the two modules should be identical to support memory
interleaving for performance gains.
Depending on how the memory modules are installed, the memory subsystem can operate in two
different modes: interleaved and single-port.
Interleaved mode (two memory modules installed): The memory modules share a common
address range. One memory module responds to even-numbered cache lines, while the other
responds to odd-numbered cache lines. This configuration offers the highest performance
because it allows the two modules to be used in a balanced fashion, reducing address conflicts.
To operate in interleaved mode, the DIMMs MUST BE INSTALLED IN PAIRS (ONE ON
EACH MODULE) AND IN THE SAME LOCATIONS ON EACH MODULE.
Single port mode (one memory module installed): The single memory module responds to all
memory addresses. The DIMMs on this single carrier need not be installed in pairs and can be
installed one DIMM at a time.
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