P58335-B21: HPE MR408i-o Gen11 x8 Lanes 4GB Cache OCP SPDM Storage Controller

Also listed as: P58543-001, P58335-001 · made by Broadcom

The HPE MR408i-o Gen11 is an OCP 3.0 form-factor tri-mode RAID storage controller built on Broadcom MegaRAID silicon, providing 8 internal lanes and 4GB flash-backed write cache. It mounts directly into the dedicated OCP mezzanine slot on HPE ProLiant Gen11 servers, preserving primary PCIe riser slots for high-speed NICs or accelerators. When acquiring used units, inspect the OCP connector contacts and verify that the firmware matches the system iLO SPDM security root.

Specifications

About the P58335-B21

P58335-B21 is HPE's MR408i-o Gen11 Storage Controller, a compact tri-mode storage controller engineered in the Open Compute Project (OCP) 3.0 mezzanine form factor. Powered by Broadcom MegaRAID technology, it incorporates 8 internal tri-mode lanes and 4GB of 72-bit DDR4-2666 Flash-Backed Write Cache (FBWC). It supports hardware RAID 0, 1, 5, 6, 10, 50, and 60 across up to 8 SAS (12Gb/s), SATA (6Gb/s), or U.3 NVMe drives. By installing into the dedicated rear OCP mezzanine slot rather than a standard PCIe riser, it preserves all primary PCIe expansion slots for graphics accelerators or high-speed fabric adapters.

Compatibility

This controller installs into the internal OCP 3.0 slot of HPE ProLiant Gen11 servers such as the DL360 Gen11, DL380 Gen11, DL385 Gen11, DL325 Gen11, and DL560 Gen11. Cabling requires server-specific SlimSAS internal cables running directly to the 8-bay front drive backplane. It requires an HPE Smart Storage energy pack (battery/capacitor) for write cache protection. It is NOT compatible with Gen10 or older servers, nor can it install in standard PCIe riser slots. The ordering part number is P58335-B21, with spare service part number P58543-001.

How to identify a genuine unit

An authentic P58335-B21 features an HPE product label with part number P58335-B21, spare number P58543-001, and an OCP 3.0 ejector latch with pull-tab. In iLO 6, the device is recognized under Storage as the HPE MR408i-o Gen11 Controller, featuring DMTF SPDM security attestation and automated firmware synchronization via HPE SPP. Non-HPE generic OCP RAID controllers will fail iLO security authentication and will not link with HPE Smart Storage Administrator tools.

Buying used

When acquiring pre-owned MR408i-o controllers, inspect the 4C+ OCP card edge connector pins for damage, scratching, or debris. Verify that the mechanical pull-tab mechanism and retention thumbscrew are in working order. Request a StorCLI diagnostic log from the seller showing that all 4GB of cache memory is functional and verify that the optional energy pack capacitor cable is supplied if write caching is required.

Reference prices (last 14 days, updated 2026-10-27)

Prices seen on public listings on the dates shown, before tax and shipping. Not an offer.

Fits these models

• HPE ProLiant DL380 Gen11
• HPE ProLiant DL360 Gen11
• HPE ProLiant DL385 Gen11
• HPE ProLiant DL325 Gen11
• HPE ProLiant DL560 Gen11

FAQ

Sources

• HPE Compute MR Controllers QuickSpecs, checked 2026-10-27