Lenovo ThinkServer RD120, Hardware Maintenance Manual

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Attention: In a dc power environment, only trained service personnel other
than Lenovo service technicians are authorized to connect or disconnect power
to the dc power supply. See the documentation that comes with each dc power
supply.
3. Remove the cover (see “Removing the cover” on page 56).
4. Remove the riser-card assembly (see “Removing the riser-card assembly” on
page 63).
5. Remove the air baffle over the DIMMs (see “Removing the DIMM air baffle” on
page 59).
Attention: To avoid breaking the retaining clips or damaging the DIMM
connectors, open and close the clips gently.
6. Open the retaining clip on each end of the DIMM connector and lift the DIMM
from the connector.
7. Replace the DIMM or remove the second DIMM of the pair.
8. 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
For information about the types of dual inline memory modules (DIMMs) that the
server supports and other information that you must consider when installing
DIMMs, see the
User’s Guide on the IBM System x Documentation CD.
v
The server comes with a minimum of two 512 MB DIMMs, installed in slots 1 and
4. When you install additional DIMMs, you must install two identical DIMMS at a
time, in the order shown in the following table, to maintain performance.
Table 16. DIMM installation sequence
Pair DIMM connectors
1 1 and 4
2 7 and 10
3 2 and 5
4 8 and 11
5 3 and 6
6 9 and 12
Note: When only one pair of DIMMs is installed in the server and the BIOS code
level is version 1.04 (GGE127A) or later, you can improve performance by
installing the DIMMs in connectors 1 and 7 instead of 1 and 4. However, because
the connectors in the pair are not on the same memory branch (see the following
illustration), Advanced ECC memory protection is disabled.
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ThinkServer RD120 server Machine Types 6444, 6445, 6446, and 6447: Hardware Maintenance Manual