Step 3 - Memory - Optional
Step 3 - Memory - Optional
Step 3 - Memory - Optional
Step 3 - Memory - Optional
Base systems do not include memory; select a minimum of 1-GB memory; this is a mandatory selection. All other systems
include one memory option.
Maximum four memory options (total of 16 DIMMs) for Model 1B (one per array)
Maximum eight memory options (total of 32 DIMMs) for Model 2B and Model 3B (two per array)
AlphaServer ES45 system includes two memory buses
AlphaServer ES45 system includes two arrays per bus
For Model 2B and Model 3B, memory options within an array must be identical
512-MB memory option (4 x 128-MB DIMMs)
MS620-AA
1-GB memory option (4 x 256-MB DIMMs)
MS620-BA
2-GB memory option (4 x 512-MB DIMMs)
MS620-CA
4-GB memory option (4 x 1024-MB DIMMs)
MS620-DB
NOTE:
NOTE:
NOTE:
NOTE: Do not order MS620-DB memory option for installation in ES45 1-GHz Model
2 (xx-68DAA-xx) system. MS620-DB memory option can only be installed in (xx-6xDBA-
xx) and (xx-6xEBA-xx) systems.
Memory performance considerations:
The AlphaServer ES45 system has two memory buses. When two or more memory options are installed, both buses are
utilized, enhancing system performance.
The AlphaServer ES45 system has two arrays per bus. Interleaved operations reduce the average latency and increase the
memory throughput. When all four arrays are populated with the same amount of memory, read-write operations are four-way
interleaved, enhancing system performance.
The following examples illustrate different ways of configuring a 4-GB system. Case C yields the best performance and is the
recommended method for configuring memory on an AlphaServer ES45 system.
ES45 System
ES45 System
ES45 System
ES45 System
(one memory option
included)
Add-on Memory Options
Add-on Memory Options
Add-on Memory Options
Add-on Memory Options
Total Memory
Total Memory
Total Memory
Total Memory
Total DIMMs
Total DIMMs
Total DIMMs
Total DIMMs
Performance
Performance
Performance
Performance
Case A
Case A
Case A
Case A - DA-68EBA-DA
(MS620-DB)
None
4-GB
4
Good
Case B
Case B
Case B
Case B - DA-68EBA-CA
(MS620-CA)
MS620-CA
4-GB
8
Better
Case C
Case C
Case C
Case C - DA-68EBA-BA
(MS620-BA)
MS620-BA + MS620-BA
+ MS620-BA
4-GB
16
Best
*
* NOTE:
* NOTE:
* NOTE:
* NOTE: Operating system and application dependent. Up to an 18% performance enhancement has been measured in Case C
over Case A.
QuickSpecs
HP AlphaServer ES45
HP AlphaServer ES45
HP AlphaServer ES45
HP AlphaServer ES45
Systems
DA - 10994 North America — Version 59 — May 7, 2007
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