Cisco UCS C220 M3, Инструкция по установке и обслуживанию

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Cisco UCS C220 Server Installation and Service Guide
OL-25760-01
Chapter 3 Maintaining the Server
Installing or Replacing Server Components
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Observe the DIMM mixing rules shown in Table 3-4 .
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Memory mirroring reduces the amount of memory available by 50% because only one of the two
populated channels provides data. When memory mirroring is enabled, DIMMs must be installed in
sets of 4, 6, or 8 as described in
Memory Mirroring, page 3-21 .
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Note the following restrictions when using UDIMMs. Even though a UDIMM might be rated at
1600 MHz, actual operational speeds are slower because of the Intel implementation.
–
In Performance Mode (1.5 V operation), UDIMMs run at 1333 MHz in 1 DPC and 2 DPC
configurations.
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In Power Saving Mode (1.35 V operation), UDIMMs run at 1066 MHz in 1 DPC and 2 DPC
configurations.
Table 3-4 DIMM Mixing Rules for C220 M3 Servers
DIMM Parameter DIMMs in the Same Channel DIMMs in the Same Bank
DIMM Capacity:
RDIMM = 4, 8, or 16 GB
LRDIMM = 32 GB
UDIMM = 4 GB
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You can mix different capacity
DIMMs in the same channel (for
example, A1 and A2).
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You cannot mix 32 GB LRDIMMs
with any RDIMM or UDIMM.
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You cannot mix 4 GB UDIMMs with
any RDIMM or LRDIMM.
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You can mix different capacity DIMMs
in the same bank. However, for optimal
performance DIMMs in the same bank
(for example, A1, B1, C1, D1) should
have the same capacity.
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You cannot mix 32 GB LRDIMMs with
any RDIMM or UDIMM.
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You cannot mix 4 GB UDIMMs with
any RDIMM or LRIMM.
DIMM Speed:
1866-, 1600-, or 1333-MHz
You can mix speeds, but DIMMs will run
at the speed of the slowest DIMMs/CPUs
installed in the channel. You can mix speeds, but DIMMs will run at
the speed of the slowest DIMMs/CPUs
installed in the bank.
DIMM Type:
RDIMMs, LRDIMMs, or
UDIMMs
You cannot mix DIMM types in a channel. You cannot mix DIMM types in a bank.
Enabling Low-Voltage DIMM Operation (Power Saving Mode)
You can enable low voltage (1.35 V) DIMM operation for all DIMMs in the server. There is a setting in
the BIOS Setup utility that you can use to change the DDR memory mode to Power Saving mode, as
described in the following procedure:
Step 1
Enter the BIOS setup utility by pressing the F2 key when prompted during bootup.
Step 2
Select the Advanced tab.
Step 3
Select Low Voltage DDR Mode .
Step 4
In the pop-up window, select either Power Saving or Performance Mode :
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Power Saving Mode–Prioritizes low-voltage memory operation.