IBM x3850 X5, Руководство по внедрению

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IBM eX5 Implementation Guide
Figure 5-14 DIMM layout on the MAX5 system board
MAX5 memory runs at 1066, 978, or 800 MHz DDR3 speeds. The memory speed is
dependent on the processor QPI speed in the HX5:
򐂰 A QPI speed of 6.4 GHz means the speed of the MAX5 memory is 1066 MHz.
򐂰 A QPI speed of 5.8 GHz means the speed of the MAX5 memory is 978 MHz.
򐂰 A QPI speed of 4.8 GHz means the speed of the MAX5 memory is 800 MHz.
Table 5-12 on page 192 indicates these memory speeds for each processor.
To see more information about how memory speed is calculated with QPI, see 2.3.1,
“Memory speed” on page 22.
5.10.2 DIMM population order
Installing DIMMs in the HX5 and MAX5 in the correct order is essential for system
performance. See 5.10.4, “Memory mirroring” on page 200 for the effects on performance
when you do not install the DIMMs in the correct order.
HX5 memory population order
As shown in Figure 5-12 on page 195, the HX5 design has two DIMMs per memory buffer
and one DIMM socket per memory channel.
For best performance, install the DIMMs in the sockets, as shown in Table 5-14 on page 197.
This sequence spreads the DIMMs across as many memory buffers as possible.
Installation methods: These configurations use the most optimized method for
performance. For optional installation methods, see the BladeCenter HX5 Problem
Determination and Service Guide at the following website:
http://ibm.com/support/entry/portal/docdisplay?lndocid=MIGR-5084529