Replacing Dimms - Cisco UCS C480 M5 Installation And Service Manual

Replacing DIMMs

Memory Mirroring
The Intel CPUs within the server support memory mirroring only when an even number of channels are
populated with DIMMs. If one or three channels are populated with DIMMs, memory mirroring is automatically
disabled.
Memory mirroring reduces the amount of memory available by 50 percent because only one of the two
populated channels provides data. The second, duplicate channel provides redundancy.
Replacing DIMMs
Identifying a Faulty DIMM
Each DIMM socket has a corresponding DIMM fault LED, directly in front of the DIMM socket. See
Diagnostic LEDs, on page 33
Step 1
Caution Never remove a CPU module without shutting down and removing power from the server.
Prepare the server for component removal:
a) Shut down and remove power from the server as described in
on page 35.
Note You do not have to pull the server out of the rack or remove the server cover because the CPU modules
are accessible from the front of the server.
Step 2
Remove an existing CPU module from the chassis:
Note Verify that the power LED on the front of the CPU module is off before removing the module.
a) Grasp the two ejector levers on the front of the CPU module and pinch their latches to release the levers.
b) Rotate both levers to the outside at the same time to evenly disengage the module from the midplane connectors.
c) Pull the module straight out from the chassis and then set it on an antistatic surface.
Step 3
Remove an existing DIMM (or DIMM blank) from the CPU module:
a) Locate the DIMM that you are removing, and then open the ejector levers at each end of its DIMM slot.
Step 4 Install a new DIMM:
Cisco UCS C480 M5 Server Installation and Service Guide
110
DIMM Capacity You can mix different capacity
DIMMs in the same channel (for
For example, 16GB,
example, A1, A2).
32GB, 64GB, 128GB
DIMM speed You can mix speeds, but DIMMs
will run at the speed of the slowest
For example, 2666 GHz
DIMMs/CPUs installed in the
channel.
DIMM type You cannot mix DIMM types in a
channel.
RDIMMs or LRDIMMs
for the locations of these LEDs.
You cannot mix DIMM capacities in
a bank (for example A1, B1). Pairs of
DIMMs must be identical (same PID
and revision).
You cannot mix DIMM speeds in a
bank (for example A1, B1). Pairs of
DIMMs must be identical (same PID
and revision).
You cannot mix DIMM types in a
bank.
Shutting Down and Removing Power From the Server,
Maintaining the Server
Internal