AC023621 Dell 16GB DDR4 3200MT/S 2RX8 ECC RDIMM Module Memory

Dell AC023621 16GB DDR4 Memory Module

The Dell AC023621 represents a specialized memory component engineered specifically for VxRail hyper-converged infrastructure systems. This 16GB DDR4 module delivers the performance, reliability, and compatibility required for demanding enterprise workloads and virtualized environments where VxRail typically operates.

Key Specifications at a Glance

This memory module operates at 3200MT/s (MegaTransfers per second) with a PC4-25600 designation, providing high-speed data transfer capabilities essential for memory-intensive applications. The module features ECC (Error Correcting Code) technology and Registered design for enhanced reliability in server environments.

Core Memory Characteristics

The Dell AC023621 is a 16GB DDR4 memory module designed for optimal performance in compatible Dell systems, particularly VxRail hyper-converged infrastructure. Understanding its technical attributes is essential for proper deployment and compatibility assessment.

Speed and Bandwidth

This module operates at 3200MT/s (MegaTransfers per second), which corresponds to a data rate of 3200 million transfers per second. The PC4-25600 designation indicates a peak bandwidth of 25,600 MB/s (25600 MB/s), calculated as 3200 MT/s × 8 bytes (64-bit data bus). This high bandwidth is crucial for handling the simultaneous data requests common in virtualized environments and database applications.

Timing Parameters

The module features CAS Latency (CL) timing of 22 cycles at its rated speed of 3200MT/s. Latency specifications are critical for understanding the delay between a memory controller request and data availability. The CL22 timing represents a balance between high-speed operation and stable performance in enterprise environments where reliability often takes precedence over absolute lowest latency.

Power Efficiency

This DDR4 memory operates at 1.2V, representing a significant power efficiency improvement over previous DDR3 generations that typically required 1.5V. The reduced voltage contributes to lower power consumption and reduced heat generation, important factors in densely populated server configurations where thermal management is critical.

Module Organization

The Dell AC023621 is configured as a 1x16GB module, meaning it provides 16GB of capacity as a single physical unit. This organization allows for flexible memory population strategies in multi-channel memory architectures, enabling administrators to optimize memory configurations based on performance requirements and budget constraints.

ECC and Registered Technology Explained

Error Correcting Code (ECC) Memory

ECC technology represents a critical reliability feature for enterprise and server environments where data integrity is paramount. The Dell AC023621 incorporates ECC capabilities to detect and correct single-bit memory errors automatically, preventing data corruption and potential system crashes that could result from memory errors.

Benefits in Enterprise Environments

In VxRail hyper-converged infrastructure and other enterprise systems, ECC protection ensures the integrity of critical business data, virtual machine states, and application information. This is particularly important for financial systems, databases, and virtualization platforms where even minor data corruption can have significant consequences. ECC memory helps maintain system stability and reduces the risk of silent data corruption that might otherwise go undetected.

Registered DDR4 Technology

The Dell AC023621 utilizes Registered (or Buffered) memory technology, distinguished from Unbuffered memory by the inclusion of a register between the memory controller and DRAM chips. This register buffers command and address signals, reducing electrical load on the memory controller.

Registered DIMM Architecture

Registered DIMMs incorporate a register chip (typically located in the center of the module) that receives command and address signals from the memory controller before relaying them to the individual memory chips. This buffering process introduces a minimal additional latency (typically one clock cycle) but enables support for higher memory capacities and more modules per channel than would be possible with unbuffered designs.

Advantages for Server Systems

The primary advantage of Registered memory in server environments like VxRail is the ability to support larger memory configurations with greater stability. By reducing the electrical load on the memory controller, Registered DIMMs allow systems to populate more memory modules while maintaining signal integrity. This capability is essential for memory-intensive applications and large-scale virtualization deployments that require substantial RAM capacity.

Dual Rank

This module is configured as Dual Rank, meaning the memory capacity is organized into two independent sets of memory chips that share the same memory interface. The memory controller can access one rank while the other is preparing for the next access, improving overall memory efficiency. Dual Rank modules generally provide better performance than Single Rank modules in most server workloads due to improved interleaving opportunities.

Physical and Form Factor Specifications

288-Pin DIMM Design

The Dell AC023621 utilizes the standard 288-pin DDR4 DIMM form factor, with a physical layout specifically designed to prevent insertion into incompatible DDR3 or future DDR5 slots. The key notch position is different from previous generations, ensuring physical compatibility only with appropriate DDR4 systems.

Module Dimensions

This RDIMM conforms to the standard DDR4 module dimensions of approximately 133.35mm (5.25 inches) in length and 31.25mm (1.23 inches) in height. The exact height may vary slightly depending on the presence of heat spreaders and specific manufacturing tolerances. These standardized dimensions ensure proper fitment in server memory slots and compatibility with retention mechanisms.

Pin Configuration and Layout

The 288-pin arrangement includes pins for data transfer, addressing, command signals, power delivery, and ground. The pinout follows JEDEC standards for DDR4 RDIMMs with specific assignments for data lines, address lines, control signals, and the additional signals required for ECC and registered functionality.

Performance Impact in HCI Environments

In hyper-converged infrastructure like VxRail, memory resources are shared between virtualization compute and storage functions. Adequate memory capacity and performance are essential for supporting both virtual machines and storage services such as deduplication, compression, and caching. The 3200MT/s speed of this module provides the necessary bandwidth for these simultaneous workloads.

Dell PowerEdge Server Compatibility

While optimized for VxRail systems, this memory module may also be compatible with various Dell PowerEdge servers that support DDR4 3200MT/s RDIMMs. Compatibility depends on the specific server model, processor generation, and BIOS version. Always consult the Dell compatibility matrix for specific server models before deployment.

Generation-Specific Considerations

This memory is typically compatible with Intel Xeon Scalable Processors of the appropriate generations (Cascade Lake, Ice Lake, or newer) that support DDR4-3200 specifications. Memory compatibility and performance are dependent on both the CPU and platform capabilities, with some systems requiring specific processor models to achieve 3200MT/s operation.

Performance Characteristics

Bandwidth Capabilities

With a theoretical peak bandwidth of 25,600 MB/s, the Dell AC023621 provides substantial data transfer capability for memory-intensive workloads. In practical applications, actual achievable bandwidth depends on numerous factors including processor capabilities, memory configuration, and workload characteristics.

Multi-Channel Performance

When installed in multi-channel memory configurations (typically dual, triple, or quad-channel depending on the platform), the aggregate memory bandwidth scales accordingly. A dual-channel configuration with two identical Dell AC023621 modules would provide approximately 51,200 MB/s of theoretical bandwidth, while a quad-channel configuration could reach approximately 102,400 MB/s.

Latency Considerations

The CL22 latency specification represents the number of clock cycles between a read command and data availability at the module outputs. At 3200MT/s, each clock cycle is 0.625ns, resulting in an absolute CAS latency of approximately 13.75ns (22 × 0.625ns). This latency profile represents an optimal balance for server workloads where consistent performance and reliability are typically prioritized over absolute lowest latency.

Real-World Performance Impact

In enterprise applications, memory performance is influenced by many factors beyond raw specifications. Memory controller efficiency, processor cache hierarchies, application access patterns, and overall system architecture all contribute to actual performance. The Dell AC023621 is engineered to deliver consistent performance under sustained server workloads rather than peak performance in synthetic benchmarks.