726874-001 HPE Smart Array P741m 4GB Controller.

Generel Specification:

• Model: HPE 726874-001 (Smart Array P741m)
• Onboard cache: 4GB DDR3/DDR4 (battery-backed or flash-backed options available depending on bundle)
• RAID levels supported: 0, 1, 5, 6, 10, 50, 60 and RAID ADM (adaptive)
• Host interface: PCIe 3.0 x8 (low-latency, high-bandwidth host connection)
• Drive support: 12Gb/s SAS and legacy 6Gb/s SATA compatibility via SAS expanders
• Advanced features: CacheVault/FBWC support, SmartCache, RAID Migration and Online Capacity Expansion (OCE)
• Management: HPE Smart Storage Administrator (SSA) and HPE Integrated Lights-Out (iLO) integration

HPE 726874-001 Smart Array P741m 4GB Controller 

The HPE 726874-001 Smart Array P741m 4GB Controller is a server-class RAID controller engineered to deliver enterprise-grade storage performance, high availability, and advanced data protection for HPE ProLiant rack and tower servers. Designed for data centers, virtualization hosts, and I/O-intensive applications, this controller combines hardware acceleration, dynamic caching, and broad RAID support to reduce latency and improve throughput across SATA and SAS disk arrays.

Controller Architecture

The P741m is purpose-built for modern storage workloads, featuring a dedicated RAID-on-Chip (RoC) with integrated processors that offload parity calculations and disk management tasks from the host CPU. The architecture permits sustained I/O performance under mixed read/write workloads and supports multiple logical drives per physical disk group.

Cache and Data Protection

The on-board 4GB cache accelerates read/write operations and optimizes random I/O. Depending on the configuration purchased, cache protection is commonly implemented using either a battery-backed write cache (BBWC) or a flash-backed write cache (FBWC)/CacheVault module, which safeguards cached data in the event of power loss. Policies such as write-back and write-through are configurable to balance performance and data integrity.

Host and Drive Interfaces

Connectivity is delivered via a PCIe 3.0 host connection (x8), offering the bandwidth required for modern NVMe-adjacent architectures and dense SAS arrays. The P741m handles 12Gb/s SAS native devices while maintaining compatibility with 6Gb/s SATA drives, making it suitable for mixed storage tiers (HDD + SSD).

RAID Capabilities and Logical Drive Management

Extensive RAID support ensures flexible deployment models—single-disk mirrored configurations for fault tolerance, RAID 5/6 for capacity-efficient redundancy, and nested RAID (10/50/60) for performance and resiliency in large arrays. The controller includes online RAID level migration and Online Capacity Expansion (OCE), allowing administrators to grow and reconfigure arrays without downtime.

Compatibility & Deployment

Server Compatibility

HPE qualifies the P741m for use with specific lines of HPE ProLiant servers (rack and tower platforms). Always consult HPE's compatibility matrix for exact supported chassis, backplane configurations, and firmware versions to ensure full interoperability — especially when mixing drive types or using third-party backplanes.

Drive and Backplane Considerations

This controller is designed to work with direct-attach drive backplanes and SAS expanders. When planning deployments, match drive carrier types, backplane cabling, and expander firmware to the controller to avoid performance or recognition issues. For large-scale arrays, use qualified SAS expanders that support the aggregated link speeds the P741m expects.

Firmware & Driver Requirements

Keeping firmware and drivers up to date is essential for stability and security. HPE releases firmware updates that often include performance enhancements, bug fixes, and new feature enablement. Use HPE Service Pack for ProLiant (SPP) or HPE Support Center to obtain validated firmware bundles and driver releases for supported OS platforms.

Performance Characteristics and Optimization

Throughput and IOPS

In typical mixed workloads, the P741m delivers high IOPS for random read/write scenarios and excellent sequential throughput when paired with SSDs or hybrid arrays. Performance scales depending on cache mode, drive type (SAS SSD vs. SATA HDD), and RAID level. RAID 10 generally yields best write performance, while RAID 5/6 provide better storage efficiency at a slight write-cost penalty.

Cache Tuning Best Practices

• Enable write-back caching when using battery/flash-backed protection to maximize write performance.
• Use write-through in environments where strict write ordering and immediate persistence are required.
• Partition cache allocation for hot data sets if the SSA allows cache partitioning to prioritize important volumes.

Performance Tuning Tips

Optimizing RAID stripe sizes, logical drive alignment, and OS-level queue depths can materially affect application performance. For databases and virtualization hosts, align filesystem block sizes and VM virtual disk settings with underlying RAID stripe configurations to reduce read-modify-write overhead.

Use Cases and Ideal Workloads

Virtualized Environments

The P741m is especially well-suited for VMware ESXi and Microsoft Hyper-V environments where multiple virtual machines generate concurrent I/O. The robust cache and RAID options enable consistent response times for consolidation use cases and VDI deployments.

Database and Transactional Systems

Transactional databases benefit from low-latency reads and cached writes; pairing the controller with enterprise-grade SAS SSDs or mixed SSD/HDD arrays achieves predictable throughput and resilience.

General Purpose File and Application Servers

For file servers, application stacks, and backup targets, the P741m offers dependable RAID protection and large-capacity scaling when combined with high-density HDDs and SAS expanders.

Management, Monitoring & Integration

HPE Smart Storage Administrator (SSA)

The Smart Storage Administrator provides a GUI and CLI interface for provisioning, monitoring, and diagnosing the controller and its logical drives. Tasks such as building arrays, configuring cache policies, scheduling patrol reads, and replacing failed drives are available through SSA.

Integration with HPE iLO

Deep integration with HPE Integrated Lights-Out (iLO) allows remote monitoring and alerting via the server management plane. Hardware events, predictive failure warnings, and drive health telemetry can be surfaced in centralized management consoles and event logs.

SNMP and Eventing

Use SNMP traps and the controller’s eventing features to feed alerts into monitoring systems (e.g., Nagios, Zabbix, SolarWinds). Timely notification of degraded RAID states or predictive drive failures minimizes downtime.

Security, Data Integrity, and Compliance

Data Protection Mechanisms

The P741m’s cache protection options prevent data loss from power failures, while firmware robustness and RAID redundancy guard against silent data corruption and disk failure. Regular firmware updates are important to mitigate against vulnerabilities and improve resiliency.

Encryption Considerations

While the controller itself focuses on RAID and caching, whole-disk encryption (SEDs) and OS-level encryption solutions can be used in tandem to meet regulatory requirements (e.g., GDPR, HIPAA). Verify compatibility of SEDs with HPE arrays and management tools prior to deployment.

How the P741m Compares with Other HPE Controllers

Compared to entry-level controllers, the P741m offers higher cache capacity, expanded RAID options, and superior performance for I/O-heavy workloads. Against HPE’s highest-end Smart Array models, differences typically include onboard cache size, support for hardware RAID accelerators, and additional management or encryption features — choose based on workload IOPS, capacity needs, and budget.

Choosing the Right Configuration

• For maximum throughput with SSDs: prioritize controllers with larger cache and faster PCIe lanes.
• For maximum capacity: favor high-density HDD arrays with RAID 6 or RAID 60 for resilient protection.
• For cost-sensitive virtualization hosts: a balanced mix of SSD cache and HDD capacity often yields the best price/performance ratio.