HP Cluster Platform Server and Workstation Overview

24. System board thumbscrew
25. System maintenance switch (SW2)
26. Hard drive backplane connector
4.13.5 Memory Options
The HP ProLiant BL685c server blade contains 16 memory expansion slots. Observe the following
guidelines when installing additional memory:
• Install only ECC PC2-5300 registered DDR2 SDRAM DIMMs that meet the following
specifications:
— Supply voltage: 1.8 V
— Bus width: 72 bits
• Install DIMMs in pairs (banks) beginning with banks farthest from each populated processor.
• Install DIMMs with the greatest capacity in the banks farthest from the processor.
• Install identical DIMMs with the same part number in a bank.
• DIMMs must be installed for processor 1.
• DIMMs installed in different banks can be of different sizes.
• For best performance, populate one bank of memory for each installed processor before
populating more than one bank for a specific processor.
• DIMMs installed in banks for processor 3 and 4 can be used only if processor 3 and 4 are
installed.
• Processors 3 and 4 can be installed without memory.
For the latest memory configuration information and Advanced Memory Protection (AMP)
options, see the HP ProLiant BL685c Server Blade User Guide.
4.13.6 Mezzanine HCA Card
In HP Cluster Platform, the HP ProLiant BL685c server blades are preconfigured with an HP 4x
DDR InfiniBand Mezzanine HCA for HP c-Class BladeSystems which works with the HP 4x
DDR InfiniBand Switch Module installed in the rear of the c–Class enclosure. For more information
on the mezzanine HCA card, see the HP ProLiant BL685c Server Blade User Guide. For more
information on the HP 4x DDR InfiniBand Switch Module, see the HP Cluster Platform InfiniBand
Interconnect Installation and User's Guide.
4.13.7 Supported Storage
The HP ProLiant BL685c supports up to two optional Hot Plug Serial Attach SCSI (SAS) drives
for a maximum of 144 GB (2 x 72 GB Serial SCSI) internal storage or up to two optional
hot-pluggable serial ATA (SATA) drives for a maximum of 120 GB (2 x 60 GB serial ATA) internal
storage.
The physical aspect of inserting and removing a disk drive is discussed in the document that
ships with the drive and in the HP ProLiant BL685c Server Blade User Guide.
Two optional Fibre Channel HBAs are supported by the HP ProLiant BL685c. Both mezzanine
circuit boards connect directly to the server blade system board. These Fibre Channel HBAs are
available via option kits and must be ordered separately.
For more detailed SAN configuration information for the server blade, see the following
documents:
• The model-specific QuickSpecs document located on the HP ProLiant c-Class server blade
products web page:
http://h18004.www1.hp.com/products/servers/proliant-bl/c-class/685c/index.html
• The HP StorageWorks SAN documentation:
http://h18006.www1.hp.com/storage/index.html
4.13 HP ProLiant BL685c Server Blade Overview 201