Technologies for the ProLiant ML570 G3 and ProLiant DL580 G3 Servers Technology Brief

2003 SP1, Microsoft Windows XP SP2, SuSe Linux Enterprise Server 9.2, or Red Hat Enterprise Linux
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For additional information about these processors, see the
Intel website or the technology brief titled
“
The Intel processor roadmap for industry-standard servers.”
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Memory architecture
The ProLiant ML570 G3 and the ProLiant DL580 G3 both use the Intel E8500 chipset architecture,
resulting in the same core technologies for the memory subsystem. However, they differ in their I/O
implementation to meet diverse customer requirements.
Background: memory banks and ranks
The term memory bank has been used to refer to more than one concept. For this paper, a memory
bank refers to a pair of DIMMs that are located in the same order in two parallel memory channels
(Figure 1). The DIMMs may be single-rank or dual-rank, which affects memory capacity and how
memory is interleaved for performance.
Figure 1. A memory bank is a pair of DIMMs. The ProLiant ML570 G3 has three memory banks; the ProLiant DL580 G3 has
two.
A single-rank DIMM is a DIMM in which all of the memory chips contribute to a single data set of 64
bits (plus the ECC bits) and are activated by the same chip-select signals.
To increase memory density, memory suppliers are producing dual-rank DIMMs. Typically, a dual-
rank DIMM is made by stacking a second set of memory chips directly on top of the first set of
memory chips. A dual-rank DIMM produces a second data set of 64 bits (plus ECC bits) and requires
two chip-selects with different signals to differentiate between the two sets of memory chips. Although
physically taking up the space of a single DIMM, a dual-rank DIMM acts as if it were two separate
DIMMs, and is considered two electrical loads by the chipset.
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This technology brief available on the ISS Technology Papers website at
http://h18004.www1.hp.com/products/servers/technology/whitepapers/adv-technology.html
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