Chapter 4. IBM System x3690 X5
131
the parallelization of workloads. When Hyper-Threading is engaged in the BIOS, for each
processor core that is physically present, the operating system addresses two. For more
information, see 2.2.2, “Hyper-Threading Technology” on page 17.
All CPU options include a heat-sink.
The x3690 X5 models include one CPU standard. All five PCIe slots are usable, even with
only one processor installed, as shown in Figure 4-8 on page 126.
The second CPU is required to access the memory in the memory mezzanine (if the memory
mezzanine is installed). The second CPU can be installed without the memory mezzanine,
but its only access to memory is through the primary CPU. For optimal performance, if two
CPUs are installed, install a memory mezzanine also.
Follow these population guidelines:
Each CPU requires a minimum of two DIMMs to operate. If the memory mezzanine is
installed, it needs a minimum of two DIMMs installed.
Both processors must be identical.
Consider the X7542 processor for CPU frequency-dependent workloads, because it has
the highest core frequency of the available processor models.
The MAX5 is supported with either one or two processors installed in the x3690 X5,
although the recommendation is to have two processors installed and memory installed in
every DIMM socket in the server to maximize performance.
If high processing capacity is not required for your application but high memory bandwidth
is required, consider using two processors with fewer cores or a lower core frequency
rather than two processors with more cores or a higher core frequency. Having four
processors can enable all memory channels and can maximize memory bandwidth. We
describe this technique in 4.8, “Memory” on page 131.
4.8 Memory
The x3690 X5 offers up to 32 DIMM sockets that are internal to the server chassis, plus an
additional 32 DIMM sockets in the MAX5 memory expansion unit.
This section covers the following topics:
4.8.1, “Memory DIMM options” on page 133
4.8.2, “x3690 X5 memory population order” on page 133
4.8.3, “MAX5 memory” on page 136
4.8.4, “Memory balance” on page 139
4.8.5, “Mixing DIMMs and the performance effect” on page 140
4.8.6, “Memory mirroring” on page 141
4.8.7, “Memory sparing” on page 143
4.8.8, “Effect on performance of using mirroring or sparing” on page 144
Implement the memory DIMMs that are internal to the x3690 X5 chassis:
16 DIMM sockets on the system planar
16 DIMM sockets in an optional memory mezzanine
Tip: The memory mezzanine is referred to in the announcement letter as the
memory
expansion card
. It is referred to as the
memory tray
, in the Installation and User’s Guide
- IBM System x3690 X5.
Summary of Contents for x3850 X5
Page 2: ......
Page 20: ...xviii IBM eX5 Implementation Guide...
Page 32: ...12 IBM eX5 Implementation Guide...
Page 34: ...14 IBM eX5 Implementation Guide...
Page 74: ...54 IBM eX5 Implementation Guide...
Page 136: ...116 IBM eX5 Implementation Guide...
Page 238: ...218 IBM eX5 Implementation Guide...
Page 392: ...372 IBM eX5 Implementation Guide...
Page 466: ...446 IBM eX5 Implementation Guide...
Page 560: ...540 IBM eX5 Implementation Guide...
Page 564: ...544 IBM eX5 Implementation Guide...
Page 578: ...IBM eX5 Implementation Guide IBM eX5 Implementation Guide...
Page 579: ......
