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Dell PERC

The Dell PowerEdge RAID Controller (PERC) is a family of hardware and software RAID controllers developed for Dell's server systems, designed to manage disk subsystems by providing , performance optimization, and through configurable RAID arrays. Introduced as an evolution from earlier Dell RAID solutions like the PERC 6 series, the modern PERC lineup spans multiple generations—Series 9 through Series 12 and 13 (the latter released in September 2025 and optimized for workloads with enhanced PCIe Gen5 NVMe RAID support)—each advancing interface technologies such as 12 Gbps , 6 Gbps , and NVMe support up to Gen5 speeds, while maintaining with prior platforms. Key features across PERC controllers include support for levels 0, 1, 5, 6, 10, 50, and 60 (with limited levels on software-only models), non-volatile flash-backed cache capacities ranging from 1 GB to 8 GB DDR4, and capabilities like hot spares, disk migration, and self-encrypting drive () integration for enhanced and reliability. PERC models are available in various form factors, including integrated (e.g., S140 software for up to 30 drives), adapter cards (e.g., H730 with 2 GB and 12 Gbps ), mini-monolithic for compact servers, and high-density options like the H965i supporting up to 240 drives with expanders, all managed via OpenManage tools or command-line interfaces for streamlined deployment in enterprise environments.

Overview

Purpose and Functionality

The Dell PowerEdge RAID Controller (PERC) is a series of RAID disk array controllers developed by specifically for its server lineup, serving as the primary interface for managing storage in enterprise environments. PERC controllers enable hardware-based configurations to ensure , optimize performance, and provide across connected drives, acting as an between the operating system and physical storage devices. They support and interfaces, accommodating both traditional hard disk drives (HDDs) and solid-state drives (SSDs) to meet diverse workload demands in data centers. At its core, PERC facilitates hardware operations that enhance protection and system efficiency by grouping multiple drives into virtual arrays, where can be striped for speed, mirrored for duplication, or protected with mechanisms to recover from failures. This results in improved (I/O) throughput, as multiple disks are accessed in parallel, and greater through redundant configurations that minimize during drive failures. These functions are enterprise-oriented, emphasizing reliability and scalability for mission-critical applications like and databases. PERC controllers are available in several form factors to suit different designs: integrated variants, such as the H-series onboard options, are embedded directly into the for compact systems, while adapter-based models, like the H965E, install via PCIe slots for expanded connectivity and higher port counts. Additionally, software RAID options in the S-series, such as the S140 or S160, leverage the host CPU and operating system for lighter management without dedicated hardware, ideal for cost-sensitive deployments. All PERC types are optimized exclusively for , ensuring seamless integration with the platform's , firmware, and management ecosystem while supporting levels like , , , and for balanced performance and protection.

Historical Development

The Dell PowerEdge RAID Controller (PERC) series originated in the early 2000s, with the introduction of the Series 5 family around 2006, designed specifically for the 9th and 10th generation servers to provide hardware-based functionality with 3 Gb/s interfaces and battery-backed options. These initial controllers marked Dell's shift toward integrated, scalable solutions for servers, supporting basic levels and up to 256 MB of to enhance data reliability and performance in growing environments. Key milestones in PERC's evolution occurred through subsequent series releases aligned with PowerEdge server generations. The Series 6 and 7, launched in the mid-2000s around 2008–2010 for 10th and 11th generation servers, introduced 6 Gb/s SAS support, non-volatile cache options up to 1 GB, and expanded RAID configurations including levels 6, 50, and 60, enabling greater fault tolerance and drive scalability up to 192 devices. In the 2010s, the Series 8 and 9 (circa 2012–2014 for 12th and 13th generation servers) adopted PCIe 2.0 and 3.0 interfaces, 12 Gb/s SAS speeds, and non-volatile cache enhancements, while the Series 10 (late 2010s, around 2017 for 14th generation servers) added NVMe support alongside larger 4–8 GB caches and up to 255 drives. The Series 11, introduced around 2020 for 15th generation servers, advanced with PCIe Gen4 and NVMe Gen4 compatibility using 12 Gb/s SAS interfaces and up to 8 GB NV cache. The Series 12, launched around 2023 for 16th generation servers, further improved performance with 22.5 Gb/s SAS interfaces, supporting up to 240 drives and 8 GB DDR4 cache for high-density hybrid environments. Dell's 2016 acquisition of significantly influenced PERC's development by integrating it into a broader ecosystem, enhancing features for hybrid cloud and data-intensive workloads through combined expertise in servers and arrays. This period also coincided with the shift in underlying chipsets, as PERC controllers transitioned from LSI/Avago designs to deeper integration with technologies following Avago's 2016 acquisition by , enabling more unified firmware and driver support across Dell's portfolio. Over time, PERC evolved from basic controllers focused on traditional disk arrays to advanced solutions that seamlessly incorporate NVMe for faster, all-flash configurations in modern data centers. As of November 2025, the Series 13 represents the flagship PERC family, introduced in 2025 for 17th generation servers, with PCIe Gen5 interfaces, NVMe Gen5 support, and optimizations for workloads including high-density NVMe configurations.

Core Technologies

RAID Support and Configurations

Dell Controllers (PERC) support a range of levels to enable , mirroring, and parity-based redundancy, depending on the controller series. Common configurations include 0 for striping across multiple disks to enhance performance without fault tolerance, 1 for mirroring data between two disks to provide full redundancy, and 10 for combining striping and mirroring to balance speed and protection. Advanced parity options encompass 5 and 50, which distribute parity across disks or sets of 5 arrays for single-drive failure tolerance with efficient capacity use, as well as 6 and 60, which employ dual parity to withstand two simultaneous drive failures, striped across disks or 6 arrays for larger-scale deployments. Virtual disks serve as the primary logical storage units in PERC setups, formed by grouping physical disks according to the selected level and configured via the controller's utility or management software. For instance, in 5, allows survival of one disk failure, with usable capacity calculated as (N-1) \times S, where N is the number of drives in the array and S is the size of the smallest drive; this formula ensures parity data consumes space equivalent to one drive. Hot spares, either global (available to any virtual disk) or dedicated (assigned to specific arrays), automatically initiate rebuilds upon detecting a failed disk, copying data from remaining drives to restore redundancy without manual intervention. The rebuild process involves the controller verifying and reconstructing data block-by-block, which can be monitored for progress and may impact system performance during execution; manual rebuilds are also supported for non-hot-spare replacements. To enable RAID configurations, systems must be set to RAID mode in the or settings, typically by selecting "RAID On" under SATA/NVMe Operation instead of AHCI, which allows the PERC controller to manage drives rather than the OS native driver. Advanced features enhance flexibility and reliability: online capacity expansion permits non-disruptive growth of virtual disk size by adding drives or utilizing free space within a disk group, supported on levels like 0, 1, 5, and 6 but not spanned arrays such as RAID 50 or 60. Consistency checks perform background verification of parity or mirror data on fault-tolerant virtual disks, correcting inconsistencies and recommended for periodic maintenance to ensure . Mixed drive support varies, with controllers accommodating both and drives in the same array where applicable, but NVMe mixing with SAS/SATA is not permitted, nor is combining HDDs and SSDs within a single virtual disk. Support for these RAID levels and features varies by PERC series, with earlier models like the Series 5 family limited to 0, 1, 5, 10, and 50, lacking 6 due to hardware constraints, while later series such as 11 and 12 provide full support for all listed levels except in entry-level variants like the H350/H355, which omit parity-based options.

Hardware Architecture and Interfaces

Dell PowerEdge RAID Controller (PERC) hardware architecture revolves around a RAID-on-Chip (ROC) processor that embeds core RAID processing capabilities directly into a single , minimizing latency and enhancing I/O efficiency. These processors, developed in partnership with LSI (now ), include early examples like the LSI 2108 ROC operating at 800 MHz for foundational data handling, evolving to more advanced variants such as the LSI 3508 (8-port) and LSI 3516 (16-port) in later implementations to support higher throughput and larger drive arrays. Cache memory serves as a high-speed for optimizing access patterns, with modern PERC controllers equipped with up to 8 GB of running at speeds of 2133 MT/s, 2666 MT/s, or 3200 MT/s to accelerate read-ahead and write-back operations. configurations support policies like write-through for or write-back for , and many models incorporate a Battery Backup Unit (BBU) to safeguard unwritten during power interruptions, providing retention for up to 24 hours; alternatively, non-volatile using offers extended preservation without batteries, retaining for years post-power loss. The interfaces of PERC controllers have progressed to accommodate increasing data demands, beginning with PCIe 1.0 in initial designs for basic connectivity and advancing to PCIe 2.0 (up to 4 GB/s unidirectional ), PCIe 3.0, PCIe 4.0 in Series 11 and 12, and PCIe 5.0 x16 in Series 13 (as of 2025) for enhanced host-to-controller transfer rates. SAS connectivity mirrors this evolution, starting at 3 Gb/s for early serial-attached and scaling to 6 Gb/s, 12 Gb/s in Series 9–11, and 22.5 Gb/s 4.0 in Series 12 and 13 (as of 2025), with full to ensure across drive generations; controllers feature internal and external mini- (SFF-8087) ports, often in x4 configurations, and compatibility with SAS expanders to daisy-chain up to eight enclosures for scalable topologies. Modern PERC controllers also PCIe NVMe drives directly, up to Gen5 speeds in Series 13. Form factors are tailored for flexibility in Dell server ecosystems, including low-profile and full-height PCIe half-length adapters for rack and tower installations, which slot directly into standard expansion bays. For modular environments, integrated MX modules provide a compact, high-density design that mounts to front bays in MX chassis, enabling seamless management without occupying PCIe slots. Power requirements emphasize efficiency, with controllers drawing low wattage to minimize overall system thermal load, typically integrating via auxiliary power connectors and relying on chassis airflow for cooling in Dell PowerEdge environments. Security features include robust support for Self-Encrypting Drives (SEDs) adhering to the TCG Enterprise standard, where encryption occurs transparently on the drive hardware using a Data Encryption Key (DEK) managed by the controller's local or enterprise key systems, ensuring data-at-rest protection without performance overhead. Complementing this, cryptographic erase—also known as secure erase—permanently destroys data accessibility by regenerating the DEK on unconfigured SEDs or Instant Secure Erase (ISE) drives, rendering prior contents irrecoverable while resetting security attributes.

Management and Software

Configuration and Monitoring Tools

Although Dell OpenManage Server Administrator (OMSA), now in end-of-life sustenance mode since September 2024 (with until September 2027), serves as a for configuring and monitoring PERC controllers, offering both local and remote access through a web-based for tasks such as virtual disk and storage array oversight, Dell recommends using the iDRAC interface or OpenManage Enterprise for current deployments. Integrated Dell Remote Access Controller (iDRAC) provides remote configuration capabilities, allowing users to access PERC configuration utilities and manage settings over a network without physical console intervention. For initial setup during system boot, the PERC configuration utility is accessed by pressing Ctrl+R for legacy series (up to Series 10), enabling users to create, delete, and manage virtual disks directly in the environment independent of the operating system. For Series 11 and later, access the utility via System Setup (press ) > Device Settings > select the PERC controller. In earlier series like PERC 4, the utility is invoked with Ctrl, facilitating basic configuration and maintenance tasks such as rescanning controllers. Additionally, the Lifecycle Controller, accessed via F10 during boot, includes wizards that guide users through volume creation and assignment for streamlined initial deployment. Command-line options enhance scripting and , with the PERC CLI utility (perccli) supporting commands such as perccli /c0/v0 set to modify virtual drive properties like access policies or settings. For , OMSA's CLI uses omreport storage commands, including omreport storage controller to view logs and status, or omreport storage pdisk to inspect physical disk health. Monitoring features in OMSA include event logs that capture controller activities and errors, exportable via the for diagnostics, alongside metrics displayed in the dashboard for real-time oversight of disk I/O and array health. Predictive failure analysis leverages (S.M.A.R.T.) to detect impending drive issues, with OMSA alerting administrators to proactive replacements through consistency checks and patrol reads. iDRAC complements this by enabling remote log access and failure notifications integrated with PERC operations. Best practices recommend performing initial RAID configuration through the boot-time configuration utility to ensure foundational stability before OS installation, followed by ongoing management via OMSA's GUI for visual monitoring or CLI for automated scripting in environments. Regular log reviews and predictive checks via these tools help maintain reliability, with iDRAC facilitating remote interventions to minimize downtime.

Firmware Updates and Drivers

Firmware updates for Dell PERC controllers are essential for maintaining , , and compatibility with evolving and operating systems. These updates can be applied through several methods, including Dell Update Packages (), which are self-extracting executables available for Windows (.exe files) and (.bin files), downloadable from the Dell support website by selecting the specific controller model. To apply a DUP, users run the file directly from the operating system or upload it via the iDRAC web interface under Maintenance > System , allowing remote deployment without physical access. Alternatively, updates can be performed using the iDRAC's Lifecycle Controller by connecting to a or local drive, or via a bootable ISO created with tools like and the Dell Repository Manager (), which enables comprehensive updates across all components in a single session. It is critical to match PERC versions to the 's and generation to prevent compatibility issues, such as failures or degraded functionality; Dell recommends verifying the update sequence in the before proceeding. Driver support for PERC controllers is integrated natively into major operating systems, ensuring seamless recognition and management of arrays. In , PERC drivers are included in the standard installation and can be updated via or 's driver packages from the support site. For distributions like and , the megaraid_sas module provides core support for PERC controllers in mode, with additional management via the PERCCLI utility installed from 's packages. includes native drivers for PERC Series 8 and later, often bundled in -customized ESXi images, while pass-through modes (such as HBA/IT mode on compatible controllers) utilize the megaraid_sas module or equivalent for direct disk access without overhead. The PERCCLI tool, supported across , , and ESXi for Series 8+, facilitates driver verification and configuration post-installation. PERC firmware versioning follows a structured scheme, with major releases indicated by the primary number (e.g., 8.x for Series 12) and sub-versions detailing builds and patches. As of October 2025, the PERC H965i Front controller's latest version is 8.14.0.0.18-14, incorporating bug fixes for stability and memory settings. options are available through DUPs or PERCCLI commands to revert to previous versions, though downgrades below 8.11.0.0.18-22 are not supported on 17th-generation servers to avoid hardware incompatibilities. Common troubleshooting scenarios for PERC involve cache-related issues, such as from power loss or improper shutdowns, which trigger error messages like "dirty " when disks are offline or missing. typically begins by restoring power and booting the system, where the controller detects preserved and prompts for or discard via the configuration utility or PERCCLI (e.g., command: /c0 [import](/page/Import) to recover data). For persistent , applying the latest via can resolve underlying memory errors, as controllers are designed to detect and mitigate single-bit issues automatically. The support lifecycle for PERC controllers aligns with that of servers, typically providing updates and support for 5-7 years from the server's general availability date, with extensions available up to 7 years. This ensures long-term maintainability, with firmware and driver releases tapering off as series age.

PERC Series Families

Series 5 Family

The Dell PERC Series 5 family, introduced in 2006, represented a significant advancement in hardware controllers for servers, providing enhanced and reliability for storage-intensive applications. These controllers were designed to support the growing demands of data centers during the mid-2000s, featuring dedicated hardware for operations and integration with emerging technology. The series marked the transition to PCIe-based architectures, enabling faster data transfer rates compared to prior PCI-based models. The primary models in the Series 5 family include the PERC 5/E for external storage expansion and the PERC 5/i, available in both integrated and adapter variants for internal configurations. The PERC 5/E focuses on external via two 4x external SAS ports, supporting up to eight drives through direct attachment or basic expanders. In contrast, the PERC 5/i models utilize two 4x internal SAS ports, making them suitable for embedded server storage without additional cabling. All models share a common hardware foundation, including the Intel IOP333 processor with XScale microarchitecture for offloading computations from the host CPU. Key specifications across the family encompass a PCIe 1.0 x8 host interface, 3 Gb/s connectivity, and 256 MB of DDR2 to read and write operations, improving throughput in multi-drive environments. backup is provided via a standard BBU on PERC 5/i models or a transportable BBU (TBBU) on the PERC 5/E for data protection during power loss, ensuring flushing to disks. These controllers support and drives up to 2 TB per disk, with a maximum of eight drives per controller without expanders, aligning with the port configuration for optimal performance in small to medium arrays. RAID support in the Series 5 family includes levels 0 (striping for speed), 1 ( for ), 5 ( for balanced capacity and ), 10 (mirrored striping), and 50 (striped arrays), with a maximum of eight physical disks per virtual disk in RAID 5 and 50 configurations to maintain efficiency. This selection catered to common enterprise needs like database hosting and file serving, where RAID 5 offered a practical trade-off between cost and protection. The controllers do not support NVMe drives, limiting them to legacy /SATA environments. As the first widespread implementation of advanced hardware in Dell's 9th and 10th generation servers—such as the 1950, 2900, 2950, and R610—the Series 5 family enabled scalable storage solutions from 2006 to 2008, replacing software-based approaches in many deployments. Compatibility is centered on these older and tower models, with the PERC 5/i integrated option commonly in systems like the 1950 and 2900 for seamless factory integration.

Series 6 Family

The Dell PERC Series 6 family, introduced around 2008, facilitated the mid-2000s shift to higher-performance storage in enterprise servers by incorporating 3 Gb/s connectivity alongside support, building on the parallel foundations of prior generations. This lineup emphasized improved data throughput and reliability for growing storage demands in data centers. Key models in the family included the PERC 6/E, an external adapter with 256 MB or 512 MB cache and battery-backed write cache, supporting up to 8 external ports via two mini- connectors; the PERC 6/I, an internal adapter with 256 MB cache and up to 8 internal ports; the SAS 6/iR, an integrated controller with no dedicated cache but support for up to 8 internal ports; and the S100, a software solution limited to 4 ports without . All hardware models used PCIe 1.0 x8 interfaces, enabling connectivity for up to 16 drives in internal configurations and 144 drives with expanders for external setups. RAID configurations across the family covered levels 0, 1, 5, 6, 10, 50, and 60 for PERC 6/E and 6/I models, with the SAS 6/iR limited to 0 and 1, and the S100 supporting 0, 1, 5, and 10 via software. A major innovation was the addition of , providing dual parity for protection against two simultaneous drive failures, which was particularly valuable for large-capacity arrays. These controllers were designed for compatibility with Dell's 11th-generation servers, including models like the R710 and T610, deployed from 2009 onward. They also introduced early support for SSDs in specific 11th-generation configurations, enabling faster and application performance while maintaining with HDDs.
ModelForm FactorCache SizePorts (SAS/SATA)Max DrivesRAID Levels Supported
PERC 6/EExternal Adapter256/512 MB8 external (3 Gb/s SAS)1440, 1, 5, 6, 10, 50, 60
PERC 6/IInternal Adapter256 MB8 internal (3 Gb/s SAS)160, 1, 5, 6, 10, 50, 60
SAS 6/iRIntegratedNone8 internal (3 Gb/s SAS)80, 1
S100SoftwareNone4 (3 Gb/s SATA)40, 1, 5, 10 (Windows only)

Series 7 Family

The Dell PERC Series 7 Family introduced expandable controllers in the late , building on prior generations with enhanced performance for in servers. These controllers supported the emerging 6 Gb/s standard, doubling the throughput of previous 3 Gb/s interfaces while utilizing PCIe 2.0 for host connectivity. Key models included the software-based PERC S300 for applications, the entry-level PERC H200 without onboard , the PERC H700 integrated or modular with battery-backed , and the external PERC H800 designed for expanded arrays. Central to the Series 7 innovations was the integration of advanced caching technologies derived from PERC 6 architecture, but with increased capacity up to 1 of non-volatile cache protected by a battery backup unit (BBU) on the H700 and H800 models. This provided improved during power loss, enabling write-back caching for better I/O performance without risking . The controllers supported up to 32 ports through expanders, allowing configurations with a maximum of 64 drives for the H700 and significantly more—up to 192—for the H800 when connected to enclosures like the PowerVault MD1200. RAID levels included 0, 1, 5, 6, 10, 50, and 60 on the H700 and H800, while the H200 was limited to 0, 1, and 10, and the S300 supported 0, 1, 5, and 10 via software on Windows systems.
ModelForm FactorCacheMax DrivesRAID LevelsKey Compatibility
S300Software/EmbeddedNone (software-managed)80, 1, 5, 10PowerEdge T110 II, embedded systems (Windows only)
H200Adapter/IntegratedNone160, 1, 1011th/12th Gen (e.g., R710, R720)
H700Adapter/Integrated/Modular512 –1 BBU64 (with expanders)0, 1, 5, 6, 10, 50, 6011th Gen (e.g., R510, R710)
H800External Adapter512 –1 TBBU192 (with enclosures)0, 1, 5, 6, 10, 50, 6011th Gen + PowerVault MD1200/MD1220
These controllers emphasized scalability for mid-range servers from 2010 to 2012, with features like self-encrypting drive (SED) support and virtual disk migration to later models, enhancing data protection and deployment flexibility in environments such as the R720. The battery-backed cache, briefly, offered protection against power failures by preserving unwritten data.

Series 8 Family

The Dell PERC Series 8 Family, introduced in the early , served as an entry-level to mid-range lineup of controllers designed for servers, emphasizing cost-effective storage solutions with enhanced performance features for small to medium workloads. These controllers supported 6 Gb/s and interfaces, PCIe 2.0 connectivity, and introduced non-volatile (NV) cache options to improve and I/O efficiency during power events, marking a refinement over prior generations by enabling better expandability and up to 192 drives when using SAS expanders. Targeted at 12th and 13th generation systems released between 2012 and 2014, such as the R730, the series provided balanced options for environments requiring reliable without premium pricing. Key models in the Series 8 Family included the software-based PERC S110 and hardware adapters like the H310, H710, H710P, and external H810. The PERC S110 was a low-cost, software solution integrated into the host CPU, supporting up to 3 Gb/s speeds across four ports with no dedicated , focusing on basic configurations for entry-level servers. It enabled levels 0, 1, 5, 10, and 50, along with features like online capacity expansion and hot-plug support, making it suitable for Windows environments and compatible with systems via Dell OpenManage tools. The hardware controllers offered more robust capabilities, with the PERC H310 providing an eight-port internal adapter at 6 Gb/s /SATA speeds over PCIe 2.0 x8, without but supporting up to 32 non- drives or levels 0, 1, 5, 10, and 50. It included innovations like physical disk via Dimmer Switch technology for in high-density setups. The PERC H710 built on this with 512 MB DDR3 and full support including levels 6, 50, and 60, accommodating up to 32 direct-attached or drives (HDDs or SSDs) and NV for protected write-back operations. For higher performance needs, the PERC H710P upgraded the cache to 1 GB , enhancing read and write throughput with features like CacheCade for SSD caching and FastPath for optimized I/O on solid-state drives, while maintaining eight internal ports and the same levels as the H710. The external PERC H810, with 1 GB cache and eight external ports via two mini-SAS connectors, extended connectivity for enclosures, supporting up to 192 drives through expanders and JBOD expansion for scalable configurations. All models in the family were compatible with major operating systems including , various distributions, and , integrating seamlessly with Dell's management suite for configuration and monitoring.
ModelTypeCachePortsMax Drives (Direct/With Expanders)RAID Levels
S110SoftwareNone4 SATAUp to 40, 1, 5, 10, 50
H310Internal AdapterNone8 internal (2x mini-SAS)32 / Up to 1920, 1, 5, 10, 50
H710Internal Adapter512 MB DDR3 NV8 internal (2x mini-SAS)32 / Up to 1920, 1, 5, 6, 10, 50, 60
H710PInternal Adapter1 GB DDR3 NV8 internal (2x mini-SAS)32 / Up to 1920, 1, 5, 6, 10, 50, 60
H810External Adapter1 GB DDR3 NV8 external (2x mini-SAS)N/A / Up to 1920, 1, 5, 6, 10, 50, 60
The NV cache innovation across the H710, H710P, and H810 models used flash-backed protection to maintain data during outages, significantly boosting performance in write-intensive scenarios compared to battery-backed alternatives, while the series' expandability via expanders allowed cost-effective scaling in rackmount servers like the R730.

Series 9 Family

The Dell PERC Series 9 family, introduced in the mid-2010s, marked a significant advancement in controllers by adopting 12 Gb/s interfaces, doubling the of previous generations to support higher-throughput applications in environments. This family includes the software-based PERC S130, internal models such as the H330, H730, and H730P, and the external H830 , all designed primarily for 13th and 14th generation servers released between 2014 and 2016. These controllers leverage PCIe 3.0 for improved I/O performance, enabling enhanced connectivity for and drives, including optimized backplanes that facilitate faster data access for SSDs in high-density configurations. Key specifications across the Series 9 models emphasize and reliability, with internal adapters like the H730 and H730P featuring up to 8 ports (configured as 2x4 internal connectors) and non-volatile () cache options of 1 or 2 DDR3, respectively, to accelerate write operations and protect data during power loss via battery backup. The H830 external extends this capability with 8 external ports, supporting up to 16 ports when paired with expanders, and includes 2 cache for demanding external storage arrays. In contrast, the PERC S130 relies on software via the system's chipset (such as C236), offering no dedicated or but supporting up to 10 drives without physical ports of its own. All models maintain backward compatibility with 6 Gb/s and 6 Gb/s , ensuring versatility across drive types. RAID support in the Series 9 family varies by model to balance performance and cost: the H330 is limited to levels 0, 1, 5, 10, and 50 without caching, suitable for basic configurations, while the H730, H730P, and H830 provide comprehensive support for levels 0, 1, 5, 6, 10, 50, and 60, enabling robust for large-scale deployments. The S130 supports 0, 1, 5, and 10 exclusively through software, with a maximum of 10 drives. Across hardware models, up to 255 drives can be managed per controller, allowing for expansive arrays in servers like the R740, where enhanced I/O paths improve overall system responsiveness. Innovations in this series focused on cache enhancements and interface speeds, exemplified by the H730P's 2 GB NV , which boosts throughput for write-intensive workloads compared to the 1 GB in the standard H730, while faster 12 /s backplanes better accommodate SSD proliferation in 13th and 14th generation systems. These features contributed to improved data protection and performance scalability, positioning the Series 9 as a bridge to more advanced paradigms in Dell's lineup.
ModelTypePortsCacheRAID LevelsMax Drives
S130SoftwareN/A (chipset-based)None0, 1, 5, 1010
H330Internal Adapter8 internalNone0, 1, 5, 10, 50255
H730Internal Adapter8 internal1 GB NV0, 1, 5, 6, 10, 50, 60255
H730PInternal Adapter8 internal2 GB NV0, 1, 5, 6, 10, 50, 60255
H830External Adapter8 external (up to 16 with expanders)2 GB NV0, 1, 5, 6, 10, 50, 60255

Series 10 Family

The Dell PERC Series 10 Family represents a significant evolution in the Controller lineup, introduced in the late to address growing demands for higher performance in enterprise storage environments. This series marked the transition toward enhanced support for modern workloads, including initial integration with NVMe technologies, while maintaining compatibility with PCIe 3.1 interfaces. Designed primarily for Dell's 14th and 15th generation servers launched between 2017 and 2019, the PERC 10 controllers emphasized improved cache capacities and flexibility for virtualized environments. The family includes both hardware-based and software-based models to cater to varying cost and performance needs. Hardware controllers comprise the PERC H345, an entry-level option with no and limited capabilities; the PERC H740P and H745, which offer 8 and 4 non-volatile () respectively for enhanced data protection during power loss; the PERC H745P MX, optimized for modular systems with integrated MX for front-bay connectivity; and the PERC H840, an external for expanded connectivity. Software options include the PERC S140 and S150, integrated controllers that leverage the host CPU for operations without dedicated hardware, supporting up to 30 NVMe drives in compatible configurations. These models utilize PCIe 3.1 x8 interfaces and support 12 Gb/s and 6 Gb/s drives, with port counts ranging from 2 internal ports on most adapters to up to 16 external ports on the H840. RAID functionality in the PERC 10 series supports levels 0, 1, 5, 6, 10, 50, and 60 on full-featured hardware models like the H740P, H745, H745P MX, and H840, enabling fault-tolerant configurations for and performance optimization. The H345 is restricted to RAID 0, 1, and 10, while software controllers S140 and S150 extend support to RAID 5 and 10 alongside basic levels, with a maximum of 255 drives per controller across configurations. Early NVMe passthrough is provided, particularly through software models and specific setups, allowing mixed /NVMe environments without full hardware RAID on NVMe drives at this stage. Cache sizes of 4-8 NV, backed by supercapacitors, improve write performance for workloads by reducing in I/O operations. Innovations in the Series 10 Family include the integration in the H745P MX, which simplifies cabling for front-bay drives in modular systems like the MX7000, and larger cache options to handle intensive tasks common in 14th/15th generation servers. These controllers are compatible with models such as the R740, R640, and R750, supporting drive expansion via expanders for scalable storage pools in mixed SAS/NVMe setups.

Series 11 Family

The Dell PERC Series 11 Family, introduced in the early , represents a significant advancement in controller technology for servers, emphasizing PCIe Gen4 support for enhanced NVMe performance. This family includes adapter-based models such as the PERC H350 and H355 for entry-level /SATA configurations, the PERC H750 and H755 for higher-performance /SATA/NVMe hybrid setups, the PERC H755N and H755 Front variants for specialized front-access deployments, and the non- HBA355 for direct-attach needs. These controllers operate on a PCIe 4.0 x8 , supporting 12 Gb/s and 6 Gb/s SATA drives alongside Gen3 and Gen4 NVMe SSDs, with an 8 GB DDR4 non-volatile cache to ensure during power loss. Key specifications highlight scalability, with up to 8 internal ports enabling support for 16 / drives without expanders or 8 NVMe drives directly; configurations with SAS expanders or PCIe switch expanders extend this to over 50 drives, limited by platform capabilities. The family supports levels 0, 1, 5, 6, 10, 50, and 60 on advanced models like the H750 and H755, while entry-level H350 and H355 limit to 0, 1, and 10; NVMe is fully integrated for high-speed SSD arrays. Innovations in this series include front-access designs on models like the H755 Front and H755N, which facilitate easier in dense environments, and optimizations for high-density NVMe setups that accelerate data-intensive workloads. Designed primarily for Dell's 15th and 16th generation servers from 2021 onward, the Series 11 Family integrates seamlessly with models like the R760, enabling high-density NVMe configurations up to 24 drives per controller in optimized setups for and applications. This compatibility builds on prior generations by prioritizing faster NVMe throughput via PCIe Gen4, supporting up to 5120 I/O queue depth for improved in environments.

Series 12 Family

The Dell PERC Series 12 Family represents the latest generation of controllers introduced in the early , designed for ultra-high-speed in environments. These controllers leverage PCIe 4.0 interfaces to deliver enhanced for modern data centers, supporting 22.5 Gbps (U.3) connectivity alongside 12 Gbps and 6 Gbps /, with compatibility for NVMe Gen3 and Gen4 drives. Key models in the Series 12 Family include the PERC H965i , H965i Front, and H965i MX for internal configurations, the PERC H965e for external connectivity, and non-RAID options such as the HBA465i /Front and the software-based PERC S160. The RAID-capable H965 series models feature 8 GB DDR4 3200 MT/s non-volatile and support up to 16 internal ports, enabling configurations for up to 16 / drives or 8 NVMe Gen4 drives per controller, subject to platform limits. The HBA465i provides direct-attach storage without overhead, while the S160 offers software for up to 30 NVMe or 8 drives, optimized for cost-effective NVMe deployments. The Series 12 controllers support including 0, 1, 5, 6, 10, 50, and 60, with features like write-back caching, read-ahead policies, and non-volatile protection to ensure during power loss. Innovations in this family include support for the compact E3.S drive at PCIe Gen4 speeds, enabling higher-density in compatible systems, and advanced caching mechanisms that improve I/O performance for demanding workloads. These controllers are tailored for Dell's 16th generation and later servers from 2023 onward, with explicit compatibility in models like the XE9680 for and tasks, while their PCIe 4.0 design positions them as future-proof for PCIe Gen5 platforms.

Series 13 Family

The Dell PERC Series 13 Family, introduced in 2025, advances controller technology for and workloads in servers, featuring PCIe Gen5 support for ultra-low latency NVMe storage. This series focuses on hardware for NVMe drives, addressing demands for dense, high-throughput configurations in modern data centers. Key models include the PERC H975i Front and H975i for internal setups, with potential variants like H975i for modular systems. These controllers use a PCIe 5.0 x16 interface and SAS5132W RAID-on-Chip , supporting up to 16 NVMe Gen5 SSDs per controller (up to 32 with dual controllers) via front MCIO connectors. Cache is integrated and supercapacitor-protected for during power events, with performance reaching 52.5 GB/s throughput and 12.5 million . Drive support includes 4.0 at 22.5 Gbps, 3.0 at 12 Gbps, at 6 Gbps, and NVMe up to Gen5 (32 GT/s) at x2 lane width. Features encompass end-to-end with Hardware Root of Trust and SPDM, flash-first NVMe , and JBOD passthrough. RAID levels supported are 0, 1, 5, 6, 10, 50, and 60, with non- options for direct attachment. The series enables configurations like up to four 5 groups of four SSDs each, optimized for training and inference tasks requiring low latency and high density. Designed for Dell's 17th generation servers, such as the R7715 and XE series, the Series 13 Family integrates with GPU-heavy setups, providing front-integrated designs for easier access in dense environments and with Gen4 platforms. As of November 2025, it positions Dell PERC for next-generation and HPC applications.
ModelTypePortsCacheRAID LevelsMax Drives
H975i FrontInternal AdapterUp to 16 internal (MCIO)Integrated NV (supercapacitor-protected)0, 1, 5, 6, 10, 50, 6016 NVMe (Gen5)
H975i AdapterInternal AdapterUp to 16 internalIntegrated NV (supercapacitor-protected)0, 1, 5, 6, 10, 50, 6016 NVMe (Gen5)

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