v The following notes apply when the server operates in non-mirroring mode
40
IBM System x3500 Type 7977: User's Guide
Minimum configuration: one pair of DIMMs
(Branch 0 works independently of Branch 1)
BR1
CH3
DIMM 10
DIMM 11
DIMM 12
Other Configuration: Multiple Pairs of DIMMs
(Branch 0 works independently of Branch 1)
BR1
CH3
DIMM 10
DIMM 11
DIMM 12
Rank 4 is used to spare any defective rank of rank 0, 2, and 3
- A rank is defined as an area or block of 64 bits that is created by using
some or all of the chips on a DIMM. For an ECC DIMM, a memory rank is
a block of 72 data bits (64 bits plus 8 ECC bits).
- The minimum memory configuration is two single-rank DIMMs that are
installed in branch 0, DIMM connector 1 (in channel 0) and connector 4 (in
channel 1); however, online-sparing is not supported with this configuration.
- To support online-sparing in branch 0, you must add a second pair of
DIMMs. The spare pair of DIMMs can be single-rank or double-rank and
must be the same speed, type, size (or larger), and technology as the
failed pair of DIMMs. The spare pair must be installed in branch 0, DIMM
connector 2 (in channel 0) and connector 5 (in channel 1). Branch 0 and
branch 1 operate independently.
(normal mode):
– DIMMs must be installed in matched pairs. If you install a second pair of
DIMMs in DIMM connector 7 and DIMM connector 10, they do not have to be
the same size, speed, type, and technology as the DIMMs in DIMM connector
CH1
CH2
DIMM 7
DIMM 4
Rank 1 is sparing to Rank 0
DIMM 8
DIMM 5
DIMM 9
DIMM 6
CH1
CH2
Rank 0 512 MB
DIMM 7
DIMM 4
Rank 1 Empty
Rank 2 512 MB
DIMM 8
DIMM 5
Rank 3 512 MB
Rank 4 1 GB
DIMM 9
DIMM 6
Rank 5 Empty
BR0
CH0
A pair of two identical
double rank modules:
Rank 0
same size, speed,
and organization
DIMM 1
Rank 1
DIMM 2
DIMM 3
BR0
CH0
A pair of two identical
single rank modules
(512MB)
DIMM 1
A pair of two identical
double rank modules
(1GB)
DIMM 2
A pair of two identical
single rank modules
(1GB)
DIMM 3