P74775-B21 HPE 4GB MR408i-p PCI SPDM Gen11 x8 Lanes Cache Plug-in Storage Controller

HPE P74775-B21 PCIe Storage Controller

The HPE P74775-B21 MR408i-p SPDM PCIe Gen4 storage controller is engineered for modern Gen11 servers requiring compact, high-throughput, and secure storage expansion. Built on a Broadcom Aero ASIC platform, this controller delivers consistent performance while maintaining flexible drive connectivity across NVMe, SAS, and SATA infrastructures.

General Information

• Manufacturer: Hewlett Packard Enterprise (HPE)
• Part Number: P74775-B21
• PCIe Gen4 x8 lane interface for high-speed connectivity
• Designed for enterprise-grade storage workloads

Technical Specifications

• Host Interface: PCIe Gen11 x8 (low-profile bracket)
• Internal Drive Interfaces: Supports SAS and SATA via internal connectors (exact ports depend on specific model variant).
• Form Factor: Standard PCIe plug-in card, typically low-profile height.

Performance and Cache Specifications

• Cache Memory: 4GB DDR4
• Cache Protection: Flash-backed write cache (FBWC) with supercapacitor
• RAID Acceleration: Dedicated hardware XOR engine for RAID 5/6

Supported Features and Standards

• RAID Levels: 0, 1, 5, 6, 10, 50, 60
• Security: SPDM for device authentication, SED (Self-Encrypting Drive) management
• Management: HPE SSA, UEFI BIOS configuration, CLI tools

Optimized Throughput and Advanced Architecture

• Delivers bandwidth reaching up to 13.7 GB/s for demanding workloads
• Powered by eight PCIe Gen4 host lanes for rapid data transfer
• Designed to handle enterprise-level storage operations efficiently

Exceptional IOPS Capabilities

• Up to 3 million random read IOPS for fast application response
• Approximately 240,000 RAID 5 random write IOPS for balanced performance
• Ideal for virtualization, databases, and high-traffic environments

Advanced Encryption and Authentication

• Compatible with self-encrypting drives for secure data at rest
• Supports DMTF SPDM for certificate-based verification
• Works seamlessly with HPE iLO 6 for trusted system communication

Flexible Management Tools

• Command-line utilities for detailed configuration
• User-friendly web interface for simplified monitoring
• Out-of-band management for remote administration

Form Factor Variants

• Standard PCIe half-height/half-length for MR216i-p and MR416i-p models
• OCP NIC 3.0 layout for MR216i-o, MR408i-o, MR408i-p, and MR416i-o

Port Configurations

• Dual 8-lane Slim SAS on MR216i-p and MR416i-p
• Low-profile Slim SAS on MR216i-o and MR416i-o
• Single 8-lane Slim SAS on MR408i-p and MR408i-o

Cache Memory Allocation

• 4 GB cache available on MR408i-o and MR408i-p controllers
• 8 GB cache included with MR416i-o and MR416i-p models
• No cache on MR216i series for entry-level storage setups

Advanced RAID Support

• RAID 0, 1, 5, 6, 10, 50, and 60 on MR408i and MR416i series
• RAID 0, 1, and 10 on MR216i controllers

Reliable Data Redundancy

• Enhanced fault tolerance for mission-critical data
• Optimized performance across multiple RAID levels

HPE P74775-B21 4GB PCI SPDM Storage Controller

The P74775-B21 MR408i-p is not merely an adapter; it is an intelligent storage engine. Its design philosophy centers on offloading storage operations from the main server CPUs, thereby freeing up valuable processing resources for core applications while delivering exceptional I/O performance.

PCIe Gen11 x8 Lanes: The High-Speed Data Highway

The controller leverages a PCI Express (PCIe) Gen11 x8 lane interface. This latest generation of PCIe technology doubles the bandwidth per lane compared to previous generations, providing a colossal pipe for data to flow between the controller, server memory, and storage devices. The x8 lane configuration ensures zero bottleneck for intensive sequential and random I/O operations, making it ideal for all-flash arrays and high-density SAS/SATA drive configurations.

Bandwidth Implications for Modern Workloads

With the bandwidth offered by PCIe Gen11 x8, the P74775-B21 MR408i-p can comfortably handle the concurrent data streams required by real-time analytics, high-frequency trading platforms, and large-scale virtualization hosts, ensuring low latency and high throughput.

Caching with 4GB of Onboard Memory

A standout feature of this controller is its integrated 4GB of DDR4 cache memory. This dedicated cache is a performance multiplier, acting as a high-speed buffer for read and write operations. Frequently accessed data (hot data) is stored in this ultra-fast cache, drastically reducing read latency. Advanced algorithms perform adaptive pre-fetching, anticipating data requests based on access patterns to further accelerate application response times.

Write Caching with Advanced Protection

For write operations, the controller acknowledges writes once data is safely in the protected cache, allowing the host application to proceed immediately. This cache is backed by supercapacitor-based flash-backed write cache (FBWC) technology, which ensures that all data in the volatile cache is permanently written to flash memory in the event of a power loss, guaranteeing data integrity.

Advanced RAID Functionality and Data Protection

The HPE MR408i-p is a full-featured RAID controller, providing robust data protection across a wide array of drive configurations. It supports RAID levels 0, 1, 5, 6, 10, 50, and 60, offering flexibility to balance performance, capacity, and redundancy.

Hardware RAID Acceleration

Unlike software-based RAID, the P74775-B21 MR408i-p performs all parity calculations, striping, and rebuild operations on its dedicated processor. This hardware acceleration is crucial for maintaining performance during drive rebuilds and ensuring that RAID 5/6 operations do not incur a significant performance penalty.

Firmware

The inclusion of SPDM (Security Protocol and Data Model) is a forward-looking feature. SPDM provides a standardized framework for device authentication and secure communication over PCIe. It enables the server to cryptographically verify the authenticity of the controller and its firmware, guarding against malicious peripherals and ensuring a trusted boot environment—a critical consideration for secure supply chain and compliance-centric deployments.

Deployment Scenarios and Ideal Use Cases

This category of controllers is targeted at specific, performance-sensitive environments within the data center and enterprise edge. For VMware vSphere, Microsoft Hyper-V, or KVM hosts, the MR408i-p provides the consistent, low-latency storage performance required to support a high number of virtual machines. Its large cache improves VM boot storms and handles mixed workloads efficiently. In VDI environments, where login storms and repetitive I/O patterns are common, the controller's caching algorithms dramatically improve user experience by caching operating system images and user profile data.

Database and Transactional Application Servers

Database servers for SQL, Oracle, and NoSQL systems are intensely I/O-bound. The P74775-B21 MR408i-p accelerates query performance by caching indexes and transaction logs, while its hardware RAID protection ensures data availability for critical line-of-business applications.

Storage-Intensive Applications and Media Workflows

Applications like video editing, rendering, and genomic sequencing involve reading and writing massive files. The high sequential throughput enabled by the PCIe Gen11 interface and large cache makes this controller suitable for such data-heavy workflows.

Management with HPE Smart Storage Administrator (HPE SSA)

Administrators can configure, monitor, and maintain the controller through the intuitive HPE SSA, available as a standalone utility, integrated into HPE iLO (Integrated Lights-Out), or via the HPE One View global management platform. This allows for remote RAID configuration, drive health monitoring, and firmware updates. The MR408i-p typically supports both SAS and SATA drives, including high-performance NVMe drives when used with appropriate expanders or in specific server backplanes. It enables the creation of large, resilient storage pools from a mix of drive technologies (HDD, SSD).

The HPE MR408i-p Controller Category

Selecting this category of storage controller is an investment in predictable performance, unwavering data integrity, and simplified lifecycle management. It is the definitive choice for IT architects and system administrators who need to. Ultimately, the HPE P74775-B21 MR408i-p Plug-in Storage Controller category represents a mature, high-performance solution for building reliable, enterprise-grade server storage that keeps pace with the demands of the most challenging workloads.

HPE ProLiant Gen11 Server Compatibility

This controller is rigorously tested and certified for use in HPE ProLiant DL, ML, and XL server families based on the Gen11 (e.g., Intel Xeon Scalable processor-based) platform. It is configured to work optimally with HPE Smart Array firmware and drivers. The P74775-B21 is designed for seamless integration with HPE's broad server portfolio, managed through a unified toolset.