Lenovo RD120 User Manual
Page 75
DIMM 1
DIMM 2
DIMM 3
DIMM 4
DIMM 5
DIMM 6
DIMM 7
DIMM 8
DIMM 9
Channel 0
Channel 1
Channel 2
DIMM 10
DIMM 11
DIMM 12
Channel 3
Branch 1
Branch 0
v
Each
DIMM
in
a
pair
must
be
the
same
size,
speed,
type,
and
technology
to
ensure
that
the
server
will
operate
correctly.
v
You
can
configure
the
server
to
use
memory
mirroring.
Memory
mirroring
stores
data
in
two
pairs
of
DIMMs
simultaneously.
If
a
failure
occurs,
the
memory
controller
switches
from
the
active
pair
to
the
mirroring
pair.
See
for
more
information
about
memory
mirroring
and
the
DIMM
installation
sequence
that
is
required.
v
The
server
supports
online-spare
memory.
This
feature
disables
the
failed
memory
from
the
system
configuration
and
activates
an
online-spare
pair
of
DIMMs
to
replace
the
failed
active
DIMM
pair.
See
for
more
information
about
online-spare
memory
and
the
DIMM
configuration
that
is
required.
v
You
can
enable
either
online-spare
memory
or
memory
mirroring,
but
not
both
at
the
same
time.
Online-spare
memory
provides
more
memory
capacity
than
mirroring.
Mirroring
provides
better
memory
protection
but
less
memory
capacity
than
online-spare
memory.
v
When
you
install
or
remove
DIMMs,
the
server
configuration
information
changes.
When
you
restart
the
server,
the
system
displays
a
message
that
indicates
that
the
memory
configuration
has
changed.
Note:
When
4
GB
or
more
of
memory
(physical
or
logical)
is
installed,
some
memory
is
reserved
for
various
system
resources
and
is
unavailable
to
the
operating
system.
The
amount
of
memory
that
is
reserved
for
system
resources
depends
on
the
operating
system,
the
configuration
of
the
server,
and
the
configured
PCI
options.
Chapter
2.
Installing
optional
devices
61