M321R4GA3BB6-CQKDG Samsung 32GB RAM PC5-38400 DDR5 4800MHz 2RX8 ECC

Samsung M321R4GA3BB6-CQKDG 32GB Memory Kit

The Samsung M321R4GA3BB6-CQKDG represents a significant advancement in server memory technology, delivering the performance, reliability, and capacity demanded by modern data centers, cloud computing infrastructures, and high-performance computing (HPC) environments. As a 32GB DDR5 Registered ECC RDIMM, this module is engineered to provide superior data integrity, enhanced bandwidth, and improved power efficiency over previous generations, making it a critical component for servers requiring unwavering stability under continuous, heavy workloads.

Core Specifications and Performance Profile

This memory module is built to the latest DDR5 SDRAM standards, offering a substantial leap in key performance metrics. It is designed for compatibility with next-generation server platforms from leading OEMs, ensuring seamless integration into new server builds and upgrade projects.

Capacity

The module features a single 32GB capacity on one stick. The configuration is denoted as 1Rx8 (Single Rank, 8 banks per rank), which optimizes signal integrity and allows for efficient population of memory channels within a server. This specific configuration balances performance and system design flexibility, enabling optimal memory population for a wide range of server applications. The "32GB (1x32GB)" denotes a single module with a total capacity of 32 Gigabytes. The "2Rx8" configuration indicates the module's internal organization: it is a dual-rank (2R) module with an x8 data width. Dual-rank modules allow for better interleaving of memory accesses, often providing a performance advantage over single-rank modules at the same density by improving memory controller efficiency.

Detailed Module Part Number Breakdown

The part number M321R4GA3BB6-CQKDG encodes the module's key attributes. 'M' indicates a memory module, '32' denotes the 32GB capacity, '1R' specifies a single-rank design, '4G' references the density of the DRAM components, and 'A3' points to the DDR5 generation and specific revision. The suffix confirms its 4800 Mbps speed, registered/ECC type, and the industrial temperature grade suitable for demanding server environments.

Speed and Latency

Operating at a data rate of 4800 megabits per second (Mbps), also classified as PC5-4800, this module offers high-throughput data transfer essential for CPU-intensive tasks. The CAS Latency (CL) is rated at CL40. In DDR5, the burst length has been doubled to 16, and the same bank refresh feature has been introduced, meaning latency comparisons to DDR4 are not direct. The overall effective performance, especially in bandwidth-limited scenarios, is substantially higher with DDR5's improved architecture. The "PC5-4800" designation is the JEDEC industry standard name for this speed grade, where "PC5" indicates DDR5 and "4800" represents the theoretical peak transfer rate in Megabytes per second per module (calculated as 4800 Mbps * 8 bytes / 8 bits ≈ 4800 MB/s). This speed forms the foundation for significantly increased system bandwidth compared to previous-generation DDR4 memory

ECC and Registered

The "ECC Registered" feature is paramount for server environments. ECC (Error-Correcting Code) is an essential technology that detects and corrects single-bit memory errors in real-time, preventing data corruption and potential system crashes. The "Registered" (or "Buffered") component refers to the presence of a register (or buffer) on the module that reduces the electrical load on the server's memory controller. This allows a single CPU to support much higher total memory capacities (often into the multiple Terabytes) and more DIMMs per channel, which is a fundamental requirement for scalable server and workstation platforms.

Bandwidth Calculation and Real-World Impact

With a data rate of 4800 Mbps and a 64-bit wide channel (plus ECC bits), a single module can provide approximately 38.4 GB/s of theoretical peak bandwidth. When installed in a multi-channel server configuration (typically 8 or 12 channels per CPU), the aggregate memory bandwidth can reach several hundred gigabytes per second, dramatically reducing data bottlenecks for applications like in-memory databases, scientific simulations, and AI/ML training.

Advanced Memory Architecture: DDR5 Enhancements

The move to DDR5 architecture brings foundational changes that benefit server reliability and performance beyond mere speed increases. The Samsung M321R4GA3BB6-CQKDG incorporates all these key innovations.

On-Die ECC (Error Correction Code)

A hallmark of DDR5 technology is the inclusion of On-Die ECC. This feature allows the memory chip to detect and correct bit errors within the DRAM chip itself before data is sent to the system-level ECC. This proactive correction at the source increases data integrity, reduces the error correction burden on the system, and contributes to higher overall reliability and component longevity.

Independent Sub-Channels

Each DDR5 DIMM features two independent, 32-bit sub-channels (with 8-bit ECC each, making 40-bit total). This architectural shift from DDR4's single 72-bit channel allows for finer-grained memory access, improving memory controller efficiency and reducing latency for certain access patterns. It effectively increases concurrency and can lead to more consistent performance.

Decision Feedback Equalization (DFE)

To maintain signal integrity at high data rates, this Samsung module utilizes advanced circuitry including Decision Feedback Equalization. DFE allows the receiver to better interpret signals by mitigating interference from previously transmitted symbols, enabling stable operation at 4800 Mbps and beyond, even in densely populated server racks with potential electrical noise.

Server-Specific Features for Maximum Reliability

This module is not a standard desktop DIMM; it incorporates specialized features that are non-negotiable for 24/7 mission-critical server operation.

Registered ECC RDIMM Design

The module is a Registered ECC RDIMM (Registered Dual In-Line Memory Module). The "Registered" component includes a register (or buffer) on the module that buffers the address and command signals between the memory controller and the DRAM chips. This reduces the electrical load on the controller, allowing for the support of a much greater number of memory modules per channel—essential for scaling memory capacity in multi-CPU servers. The ECC (Error Correcting Code) functionality can detect and correct single-bit errors and detect multi-bit errors, preventing data corruption and system crashes.

Power Management Integrated Circuit (PMIC)

DDR5 modules relocate the voltage regulation from the motherboard to the memory module itself via an integrated PMIC. This provides cleaner, more stable power delivery to the DRAM chips, improving signal integrity and noise immunity. The PMIC also enhances power efficiency, a critical factor in large-scale data center deployments where operational expenditure (OPEX) on power is a major concern. The nominal operating voltage is a low 1.2V.

Parity Protection

Beyond data ECC, this server-grade module includes parity protection on the command and address buses. This ensures that not only the stored data but also the instructions sent *to* the memory (commands like read, write, activate) are protected from corruption, adding another layer of system-level robustness.

Physical Design and Compatibility

The module adheres to strict industry-standard form factors to ensure broad compatibility with next-generation server platforms.

288-Pin RDIMM Form Factor

The module utilizes a 288-pin connector layout specific to DDR5 RDIMMs. The pin arrangement and notch key position are physically different from DDR4 DIMMs, preventing accidental insertion into an incompatible motherboard socket. It is crucial to verify that the target server platform explicitly supports DDR5 Registered ECC RDIMMs.

Thermal Sensor and Heat Spreader

To monitor operational health within the server's thermal environment, the module is equipped with a Serial Presence Detect (SPD) Hub that includes a temperature sensor. This allows the system's baseboard management controller (BMC) to monitor memory temperature and adjust cooling profiles accordingly. The module features a robust aluminum heat spreader that effectively dissipates heat, maintaining optimal operating temperatures and ensuring sustained performance during prolonged heavy use.

Target Applications and Use Cases

The Samsung M321R4GA3BB6-CQKDG is purpose-built for environments where data accuracy, system uptime, and high throughput are paramount.

Data Center and Cloud Servers

In virtualized cloud environments and large-scale data centers, this memory supports high-density virtualization, enabling more virtual machines per physical host with reliable performance. Its ECC and registered features are essential for maintaining service level agreements (SLAs) and ensuring tenant isolation and stability.

High-Performance Computing (HPC)

For scientific research, financial modeling, and artificial intelligence workloads, the high bandwidth of DDR5 at 4800 Mbps accelerates data movement between CPUs and memory. This reduces computation time for large datasets, directly impacting research cycles and time-to-insight for complex models.

Enterprise Databases and ERP Systems

Mission-critical database servers running Oracle, SAP HANA, Microsoft SQL Server, or other in-memory databases require the extreme capacity, bandwidth, and unwavering data integrity provided by this Samsung RDIMM. It helps ensure transaction integrity and supports real-time analytics on large datasets.