NEC Express5800/120Rh-1 Configuration Manual page 8

Memory Mirroring / On-line Spare Memory
The 120Rh-1 supports memory mirroring and online spare memory as standard to improve memory reliability.
• Follow the rules for installing memory DIMMs.
• To enable online spare memory, go to BIOS Setup.
• You cannot use the standard memory mode, memory mirroring, and online spare memory at the same time in the same
system.
Standard memory mode
Memory branch #0
MB
Configuration
Memory branch #1
Not redundant
Functions
(default)
Capacity Same as physical capacity
Not removable during operation
Hot plug
Not redundant
Reliability
Requirements for Memory Mirroring
• The branch #0 and #1 must be identical in DIMM configuration
(size and position).
• No mirroring can be configured between the DIMMs on the same
memory branch.
Memory Branch #0
Group#1
The mirrored branch
DIMM#11
must have the same
DIMMs in the same
positions as
configured on the
Group#3
primary branch.
DIMM#12
Group#5
DIMM#13
Memory combinations for memory mirroring
Group#1 Group#2 Group#3
DIMM#11,#21 DIMM#31,#41 DIMM#12,#22
combination1 2GB 2GB
combination2 2GB 2GB 1GB
combination3 2GB 2GB 2GB
combination4 2GB 2GB 1GB
combination5 2GB 2GB 1GB
combination6 2GB 2GB 2GB
2GB
combination7 2GB 4GB
combination8 2GB 2GB 2GB
combination9 2GB 2GB 1GB
combination10 2GB 2GB 4GB
combination11 2GB 2GB 2GB
combination12 2GB 2GB 4GB
combination13 2GB 2GB 4GB
combination14 4GB 4GB 4GB
combination22 8GB 8GB 8GB
Memory branch #0
MB
Memory branch #1
Data mirrored between memory branch #0
Half the physical capacity
Not removable during operation
Chipset (Memory Controller)
Memory Branch #1
Group#2
=
DIMM#21 DIMM#31 DIMM#41
Group#4
=
DIMM#22 DIMM#32 DIMM#42
Group#6
=
DIMM#23 DIMM#33 DIMM#43
2GB
Physical
Group#4 Group#5 Group#6
capacity
DIMM#32,#42 DIMM#13,#23 DIMM#33,#43
4GB
1GB 6GB
2GB 8GB
1GB 1GB 1GB 8GB
1GB 2GB 2GB 10GB
2GB 1GB 1GB 10GB
4GB 12GB
2GB 2GB 12GB
2GB
1GB 4GB 4GB 14GB
4GB 1GB 1GB 14GB
2GB 4GB 4GB 16GB
4GB 2GB 2GB 16GB
4GB 4GB 4GB 20GB
4GB 4GB 4GB 24GB
8GB 8GB 8GB 48GB
Memory Mirroring
Mirrored
Mirrored set
and #1
Fully redundant
Requirements for Online Spare Memory
• Memory sizes must be the same across memory groups on the
same memory branch.
• Memory sizes may vary by memory branches.
• The memory groups farthest from the memory branches are spares.
MemoryBranch#0
Group#1
Memory Mirroring
and Online Spare
Group#3
Memory are not
available at the same
time. Group#5
Memory combinations for Online Spare Memory
:standard
Logical
Config. Group#1
capacity
DIMM#A1,#B1
2GB
1 1GB
3GB
2 1GB
4GB
3 2GB (std.)
4GB
4 2GB (std.)
5GB
5 4GB
5GB
6 4GB
6GB
6GB 7 8GB
8 8GB
7GB
7GB
Your logical memory capacity is calculated using one of the following two formulas:
8GB
When you are using 1GB Memory Module Set
When you are using 1GB Memory Module Set [
8GB
[Logical capacity] [Logical capacity]
10GB = [Total of physical capacities]
= [Total of physical capacities
12GB
When you are using Standard 1GB memory or
Additional 2GB/4GB//8GB Memory Module Set [N8102-310/-311/-312]:
[Logical capacity]
24GB
= [Total of physical capacities] – [Physical capacity per memory group]] / 2
On-line Spare Memory
Memory branch #0
In the event
of a memory
failure, a
MB
spare DIMM
takes over a
faulty DIMM
Memory branch #1
A faulty DIMM automatically fails over to a
spare memory on the same memory branch.
Physical capacity does not include spare
memory.
Not removable during operation
A faulty DIMM automatically fails over to a
spare memory on the same memory branch.
MemoryBranch#1
Group#2
Group#4
Group#6
Memory branch #0
Group#2 Group#3 Physical
DIMM#A2,#B2 DIMM#A3,#B3
capacity
1GB 2GB
1GB 1GB 3GB
2GB 4GB
2GB 2GB 6GB
4GB 8GB
4GB 4GB 12GB
8GB 16GB
8GB 8GB 24GB
[N8102 N8102- - 309]:
309]:
] – [Physical capacity per memory group]
– [Physical capacity per memory group]
120Rh-1
online.
Logical
capacity
1GB
2GB
3GB
5GB
6GB
10GB
12GB
20GB