Dimm installation sequence, Memory mirroring, Dimm – Lenovo 3797 User Manual
Page 82: Installation, Sequence, Memory, Mirroring
DIMM
installation
sequence
The
server
requires
at
least
one
DIMM
per
microprocessor.
The
server
comes
with
a
minimum
of
two
1
GB
DIMMs,
installed
in
connectors
3
and
6.
(Connectors
3
and
6
are
the
farthest
connectors
for
channels
0
and
1
of
microprocessor
1.)
When
you
install
additional
DIMMs,
install
them
in
the
order
shown
in
to
maintain
performance.
Important:
If
you
have
configured
the
server
to
use
memory
mirroring,
do
not
use
the
order
in
go
to
and
use
the
installation
order
shown
there.
Table
8.
DIMM
installation
sequence
for
non-mirroring
(normal)
mode
Installed
microprocessors
DIMM
connector
population
sequence
Microprocessor
socket
1
Install
the
DIMMs
in
the
following
sequence:
3,
6,
8,
2,
5,
7,
1,
4
Microprocessor
socket
2
Install
the
DIMMs
in
the
following
sequence:
11,
14,
16,
10,
13,
15,
9,
12
Memory
mirroring
Memory-mirroring
mode
replicates
and
stores
data
on
two
pairs
of
DIMMs
within
two
channels
simultaneously.
If
a
failure
occurs,
the
memory
controller
switches
from
the
primary
pair
of
memory
DIMMs
to
the
backup
pair
of
DIMMs.
You
must
enable
memory
mirroring
through
the
Setup
utility.
For
details
about
enabling
memory
mirroring,
see
When
you
use
the
memory
mirroring
feature,
consider
the
following
information:
v
When
you
use
memory
mirroring,
you
must
install
a
pair
of
DIMMs
at
a
time.
One
DIMM
must
be
in
channel
0,
and
the
mirroring
DIMM
must
be
in
the
same
connector
in
channel
1.
The
two
DIMMs
in
each
pair
must
be
identical
in
size,
type,
rank
(single,
dual,
or
quad),
and
organization.
They
do
not
have
to
be
identical
in
speed.
The
channels
run
at
the
speed
of
the
slowest
DIMM
in
any
of
the
channels.
See
for
the
DIMM
connectors
that
are
in
each
pair.
v
Channel
2,
DIMM
connectors
8
,7,
15,
and
16
are
not
used
in
memory-mirroring
mode.
v
The
maximum
available
memory
is
reduced
to
half
of
the
installed
memory
when
memory
mirroring
is
enabled.
For
example,
if
you
install
64
GB
of
memory,
only
32
GB
of
addressable
memory
is
available
when
you
use
memory
mirroring.
The
following
illustration
shows
the
memory
channel
interface
layout
with
the
DIMM
installation
sequence
for
mirroring
mode.
The
numbers
within
the
boxes
indicate
the
DIMM
population
sequence
in
pairs
within
the
channels,
and
the
numbers
next
to
the
boxes
indicate
the
DIMM
connectors
within
the
channels.
For
example,
the
following
illustration
shows
that
the
first
pair
of
DIMMs
(indicated
by
ones
(1)
inside
the
boxes)
should
be
installed
in
DIMM
connector
3
on
channel
0
and
DIMM
connector
6
on
channel
1.
DIMM
connectors
7,
8,
15,
and
16
on
channel
2
are
not
used
in
memory-mirroring
mode.
66
ThinkServer
RD220
Types
3729,
3779,
3797,
and
3798:
Installation
and
User
Guide