Lenovo BladeCenter HS23 1929 Problem Determination And Service Manual Download

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Step 9. If you are instructed to return the DIMM, follow all packaging instructions, and use any packaging

materials for shipping that are supplied to you.

Installing a memory module

Use these instructions to install memory modules in the blade server.

The blade server has a total of sixteen direct inline memory module (DIMM) slots. The blade server supports
very low profile (VLP) DDR3 DIMMs with error code correction (ECC) in 4 GB, 8 GB, and 16 GB capacities.
For a list of supported DIMMs for the blade server, see Chapter 3 “Parts listing” on page 29.

After you install or remove a DIMM, you must change and save the new configuration information by using
the Setup utility. When you turn on the blade server, a message indicates that the memory configuration has
changed. Start the Setup utility and select

Save Settings

(see “Setup utility menu” on page 12 for more

information) to save changes.

The memory is accessed internally through the system using four channels per microprocessor. Each
channel contains two DIMM connectors. The following table lists each channel and which DIMM connectors
belong to the channel.

Table 2. Memory channel configuration

Memory channel

DIMM connector (microprocessor
1)

DIMM connector (microprocessor
2)

Channel 0

7 and 8

15 and 16

Channel 1

1 and 2

13 and 14

Channel 2

3 and 4

9 and 10

Channel 3

5 and 6

11 and 12

Depending on the memory mode that is set in the Setup utility, the blade server can support a minimum of 4
GB and a maximum of 128 GB of system memory on the system board in a blade server with one
microprocessor. If two microprocessors are installed, the blade server can support a minimum of 8 GB and a
maximum of 256 GB of system memory. There are four different memory modes:

•

Independent channel mode:

Independent channel mode gives a maximum of 128 GB of usable memory

with one microprocessor installed, and 256 GB of usable memory with two microprocessors installed
(using 16 GB DIMMs). The DIMMs can be installed without matching sizes. See the table below for the
memory installation order.

•

Rank sparing mode:

In rank sparing mode, one rank of a DIMM in each populated channel is reserved as

spare memory. The spare rank is not available as active memory. When the active rank memory fails, its
content is copied to the spare rank memory which becomes active. The memory set aside for spare is one
rank per channel. The size of a rank varies depending on the DIMMs installed. The DIMM population
ordering for rank sparing mode is the same as that for independent channel mode.

Table 3. DIMM population sequence for independent-channel mode and rank-sparing mode

One microprocessor installed

Two microprocessors installed

DIMM connectors 1, 7, 3, 5, 2, 8, 4, and 6

DIMM connectors 1, 16, 7, 14, 3, 9, 5, 11, 2, 15, 8, 13, 4,
10, 6, and 12

•

Mirrored channel mode:

In mirrored channel mode, the memory contents on channel 0 are duplicated in

channel 2, and the memory contents of channel 1 are duplicated in channel 3. The effective memory
available to the system is only half of that installed. The maximum available memory (with 16 GB DIMMs)
is 64 GB for a single microprocessor system and 128 GB for a dual microprocessor system.

Chapter 4

Removing and replacing blade server components