405836-001 - 256MB DDR2 x40 BBWC Cache Memory Board for Smart Array P400 and P400i

The 405836-001 is a 256MB 40-bit DDR2-533 ECC-protected cache memory board designed for Smart Array P400 and P400i RAID controllers. It installs directly into the controller’s proprietary cache connector and supports read-ahead caching and battery-protected write-back caching when used with a functional compatible battery and the correct cable.

This listing includes the 256MB cache memory board only. The RAID controller, battery and battery cable are not included.

Technical Specifications

• Part Number: 405836-001
• Service Description: SPS-BD SA DDR2 x40 256MB
• Product Type: RAID controller cache memory board
• Cache Capacity: 256MB
• Memory Technology: DDR2-533 SDRAM
• Data Width: 40-bit
• Error Protection: ECC-protected cache
• Compatible Controllers: Smart Array P400 and P400i
• Installation Type: Proprietary controller cache daughterboard
• Cache Functions: Read-ahead caching and write-back caching
• Backup Method: External battery-backed write cache
• Compatible Battery Type: 4.8V Ni-MH RAID controller battery
• Supported RAID Levels: RAID 0, RAID 1, RAID 1+0 and RAID 5
• Advanced RAID Support: RAID 6 with ADG requires an operational battery-backed cache configuration
• Upgrade Path: Supports replacement with the 405835-001 512MB 72-bit cache module
• Included: 256MB cache memory board only
• Not Included: RAID controller, battery or battery cable

Interchangeable / Replacement Part Numbers

• Direct Service Spare: 405836-001
• Assembly Number: 012764-004
• Board-Level Reference: 013125-000
• P400i 256MB Cache Option Reference: 405139-B21

The option reference may have been supplied in service or upgrade packaging. Verify the installed board label when an exact service-spare match is required.

Related Controller and Component Part Numbers

• P400 256MB Controller Options: 405132-B21, 405133-B21
• P400 256MB Factory-Integrated Controller: 405160-B21
• P400 DL38x Low-Profile Controller: 405161-B21
• P400 Controller Board Spares: 405831-001, 405832-001, 447029-001, 504022-001, 504023-001
• 512MB Cache Upgrade Spare: 405835-001
• 512MB Cache Assembly: 012764-003
• 512MB Cache Upgrade Option: 405148-B21
• Compatible Battery References: 398648-001, 381573-001, 012695-001
• Battery Regulatory Model: HSTNM-B011
• Battery Upgrade Kit: 383280-B21
• 11.5-Inch Battery Cable: 409124-001, 408658-001
• 24-Inch Battery Cable: 409125-001, 408658-002
• 24-Inch Battery Attach Kit: 417836-B21
• Complete P400 512MB Controller Kit: 405162-B21
• Related P400 512MB Controller Option: 411064-B21
• P400 Internal SAS Data Cable: 361316-011

The controllers, battery, cables and complete controller kits are related components. They are not direct replacements for the 405836-001 memory board.

Related Parts Available

• Controller Board: 504022-001 Smart Array P400 PCIe x8 RAID Controller Board
• 512MB Cache Upgrade: 405835-001 512MB BBWC Cache Memory Module
• Compatible Battery: 398648-001 4.8V Ni-MH RAID Controller Battery Pack
• 11.5-Inch Battery Cable: 408658-001 / 409124-001 16-Pin Battery Cable
• 24-Inch Battery Cable: 408658-002 / 409125-001 16-Pin Battery Cable
• Internal SAS Data Cable: 361316-011 24-Inch SAS HDD Data Cable
• Complete 512MB Controller Kit: 405162-B21 Smart Array P400 SAS PCIe RAID Controller Kit
• P400 Controller Option: 405133-B21 Smart Array P400 SAS RAID Controller

✅ Confirmed Compatibility

Compatibility follows the installed RAID controller rather than the server model alone. The system must contain a Smart Array P400 or P400i controller with the replaceable 256MB cache-board connection.

✔️ Smart Array Controllers: P400 and P400i configurations supporting the 256MB 40-bit DDR2 cache board
✔️ ProLiant Blade Systems: BL480c configurations equipped with the P400i controller and replaceable 256MB cache
✔️ ProLiant DL100 Series: DL160 G5, DL160 G5p, DL165 G5, DL165 G5p, DL180 G5 and DL185 G5 configurations equipped with a P400 controller
✔️ ProLiant DL300 Series: DL320 G4, DL320 G5, DL320 G5p, DL320s, DL360 G5, DL365 G5, DL380 G5, DL385 G2, DL385 G5, DL385 G6, DL385 G7 and DL388 G7 configurations equipped with a P400 or P400i controller
✔️ ProLiant DL500 Series: DL580 G4, DL580 G5, DL585 G2 and DL585 G5 configurations equipped with a P400 controller
✔️ ProLiant DL700 and DL900 Series: DL785 G5, DL785 G6 and DL980 G7 configurations equipped with a P400 controller
✔️ ProLiant ML300 Series: ML310 G4, ML310 G5, ML310 G5p, ML350 G5, ML350 G6 and ML370 G5 configurations equipped with a P400 controller
✔️ ProLiant ML500 Series: ML570 G4 configurations equipped with a P400 controller
✔️ Integrity Systems: BL860c, rx2660 and rx3600 configurations equipped with a P400 or P400i controller
✔️ LeftHand Storage Systems: P4000 SAN Solutions, P4000 G2 SAN Solutions and NSM Storage configurations using a P400 controller
✔️ StorageWorks Systems: X1800sb G2 Network Storage Blade, 1200 All-in-One Storage System, All-in-One SB600c Storage Blade and 6000 Virtual Library System configurations using a P400 or P400i controller
✔️ Additional Storage Platforms: SB40c Storage Blade, High Availability Storage Server, Data Protection Storage Server and StoreOnce configurations using a P400 or P400i controller

☑️ Key Features

☑️ 256MB DDR2-533 controller cache capacity
☑️ 40-bit memory architecture with ECC protection
☑️ Direct replacement for 405836-001 and 012764-004 cache boards
☑️ Supports both P400 and integrated P400i controller configurations
☑️ Supports read-ahead caching for improved storage performance
☑️ Supports protected write-back caching with a functional battery and cable
☑️ Can enable RAID 6 with ADG when the controller has a valid BBWC configuration
☑️ Supports online array expansion and logical drive extension when BBWC requirements are satisfied
☑️ Supports RAID-level and stripe-size migration when permitted by controller firmware
☑️ Upgradeable to the 512MB 72-bit 405835-001 cache module

⚙️ Fit Notes

• This is a proprietary RAID controller cache board and is not a standard desktop or server memory DIMM.
• Verify that the installed controller is a P400 or P400i before ordering.
• The 405836-001 uses a 256MB 40-bit design. The 405835-001 upgrade uses a different 512MB 72-bit design.
• Install only one supported cache board in the controller. The 256MB and 512MB modules are not used together.
• Protected write-back caching requires a functional compatible battery and the correct battery cable.
• Without a valid battery, the controller may operate in write-through mode and disable RAID 6 with ADG.
• A failed, discharged or missing battery can produce a cache or battery warning even when the memory board is functional.
• Battery-cable length varies by server chassis. Compare the existing cable before choosing the 11.5-inch or 24-inch version.
• Replacing the cache board will not correct a failed battery, damaged cable or defective controller.
• Cache modules used by P410, P410i, P411 and later controller generations are physically and electrically different.
• Power down the system and use proper electrostatic-discharge precautions during installation.