HP ProLiant AMD-based 300-series G7 servers

Direct Connect architecture 2.0
Unlike front-side bus architecture, Direct Connect integrates the memory controller into the processor
and directly connects CPUs to the I/O subsystem and other processors (Figure 2). Direct Connect
architecture uses direct HyperTransport links between CPUs, between CPU and I/O, and between
CPU and memory. Direct Connect architecture currently scales up to 12 cores to provide superior
memory and I/O capability, near native virtualization performance, and a range of power bands
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that place a priority on low power consumption.
Figure 2. Block diagram of Direct Connect 2.0 architecture in the AMD 6100 series processors
72 Bit
72 Bit
72 Bit
72 Bit
L3B
L3B
5.2GB/s
L3A
L3A
5.2GB/s
L1
L0
10.4GB/s
L2
L1
10.4GB/s
L2
L1
10.4GB/s
AMD Opteron 6100-series
processor
HT3 L2
HT3 HT3 HT3 HT3
8 or 12 Cores
DDR3
512 KB shared cache per core
12 MB L2 cache
HyperTransport technology
HyperTransport is a point-to-point interconnect that is designed to connect the processors directly and
to connect each processor to its dedicated memory banks, as well as to other I/O chipsets.
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Compared to a shared, parallel front-side bus, the advantages of HyperTransport include no
overhead for bus arbitration and easier signal integrity maintenance, which results in a scalable, high-
bandwidth architecture.
Each16-bit (2-byte) HyperTransport link is double-pumped to perform two data transfers per clock
cycle. From HyperTransport 1.0 (HT1) in 2001 to HyperTransport 3.1 in 2008, the maximum clock
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Power bands refer to a new metric developed by AMD to reflect power consumed by the processor and its integrated memory
controller during peak workloads. This metric is based on AMD’s measurement of Average CPU Power (ACP). For more
information on ACP, see the whitepaper at www.amd.com/us-
en/assets/content_type/white_papers_and_tech_docs/43761C_ACP_WP.pdf
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HyperTransport Technology was invented at AMD with contributions from industry partners and is managed and licensed by
the HyperTransport Technology Consortium, a Texas non-profit corporation.
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