HMA84GL7AFR4N-VK Hynix 32GB DDR4 2666MHZ PC4-21300 CL19 ECC RDIMM Memory Module

• Manufacturer: Hynix
• Part Number: HMA84GL7AFR4N-VK
• Module Type: LRDIMM (Load-Reduced DIMM)

Hynix HMA84GL7AFR4N-VK Memory Module Module

Every segment of the part number reveals a key specification. HMA84GL7AFR4N-VK breaks down as follows: HMA denotes Hynix Memory Module, 84G indicates a 64Gb (gigabit) component density, L stands for 1.2V Low Voltage, 7 refers to the component organization, A is the revision, F designates the FBGA package, R4 confirms it's a Registered (RDIMM) type with LRDIMM features, N stands for Normal Halogen-free, and VK specifies the speed grade (2666MHz) and other internal timings. This nomenclature is a roadmap to the module's capabilities, crucial for ensuring compatibility and meeting specific performance requirements..

Capacity: 32GB

The 32GB capacity per module is a critical feature for maximizing total system memory without consuming excessive physical slots. In a typical dual-processor server platform with 24 DIMM slots, utilizing 32GB modules like the HMA84GL7AFR4N-VK enables a staggering 768GB of total RAM per server. This module achieves its high density through the use of advanced memory chips (DRAM components) with high gigabit density and the Dual RankX4 organization, which optimizes the internal data paths for efficient addressing of large memory spaces.

DDR4-2666 (PC4-21300) Speed and Bandwidth

Operating at a data rate of 2666 Megatransfers per second (MT/s), this module belongs to the DDR4 generation's performance tier. The designation PC4-21300 refers to its theoretical peak bandwidth: 21,300 MB/s (or approximately 21.3 GB/s). This is calculated as 2666 MT/s * 8 bytes (64-bit data path) = 21,328 MB/s. In a multi-channel server architecture (e.g., 6-channel or 8-channel), this bandwidth is multiplied, feeding data-hungry CPUs and reducing processing latency. The 2666MHz speed offers a significant performance uplift over older 2133MHz or 2400MHz server memory, improving overall throughput for virtualization, in-memory databases, and complex computational tasks.

PC: PC4-21300

The Hynix HMA84GL7AFR4N-VK LRDIMM Memory Module is designed to operate at PC4-21300 speed. This designation determines the module's data transfer rate and compatibility with specific systems.

ECC (Error-Correcting Code) for Data Integrity

ECC is non-negotiable for enterprise systems. It adds extra bits to each data word to detect and, crucially, correct single-bit errors on the fly. It can also detect multi-bit errors. This prevents silent data corruption—where data changes without the system knowing—which can corrupt databases, crash applications, or lead to erroneous computational results. In 24/7 operational environments, ECC provides the foundational layer of data reliability that the HMA84GL7AFR4N-VK is built upon.

Speed: 2666MHZ

The HMA84GL7AFR4N-VK LRDIMM Memory Module boasts a speed of 2666MHz. This high-speed memory ensures faster data transfer and improved system responsiveness, making it suitable for various computing needs.

Moving Beyond RDIMM: The LRDIMM Advantage

An LRDIMM goes a crucial step further. It replaces the register with an ISODIMM buffer (or Memory Buffer) that buffers not only the address/command lines but also the data lines (DQ). This virtually eliminates the electrical load on the memory controller from the DRAM chips themselves. The controller sees only the buffer's load, regardless of how many DRAM chips are on the module or their rank configuration.

Mixing and Matching Memory Modules

Best practice in enterprise environments is to populate memory channels with identical modules—same part number, capacity, speed, rank, and technology. Mixing LRDIMMs with RDIMMs or unbuffered DIMMs (UDIMMs) is generally not supported. Mixing different capacities or speeds within a system may be supported but will force all modules to run at the speed and timings of the slowest module, potentially negating the performance benefits of the Hynix 2666MHz module.

Thermal Management

While operating at an efficient 1.2V, a fully-populated server with 24 or 32 of these 32GB modules represents a significant power and thermal load. Adequate server cooling (high-performance fans and optimal airflow configuration) is essential to prevent thermal throttling, which can reduce memory speed and increase latency. Enterprise servers are designed with these thermal profiles in mind, but proper deployment in a climate-controlled data center remains critical.

DDR: DDR4

The Hynix HMA84GL7AFR4N-VK LRDIMM Memory Module is based on DDR4 (Double Data Rate 4) technology. DDR4 is the latest generation of memory technology and offers several advancements over its predecessors. DDR4 offers higher bandwidth compared to previous generations, allowing for faster data transfer rates. This increased bandwidth enables quicker access to stored data and supports higher memory speeds, resulting in improved overall system performance and responsiveness.

Reliability

This Hynix LRDIMM contributes directly to the RAS characteristics of the overall server system. Its ECC protects data, its LRDIMM design ensures reliable operation at full population, and its industry-standard 288-pin design allows for hot-swap replacement in servers that support it, minimizing downtime. These features are integral to achieving "five nines" (99.999%) of uptime demanded by modern enterprises.

Compatibility

The HMA84GL7AFR4N-VK is designed for specific Intel Xeon Scalable Processors (e.g., Skylake-SP, Cascade Lake-SP, and newer) and compatible AMD EPYC platforms that officially support DDR4-2666 LRDIMMs. It is imperative to consult the server manufacturer's (Dell EMC, HPE, Lenovo, Cisco, Supermicro, etc.) qualified vendor list (QVL) or memory compatibility guide to confirm this exact part number or its equivalent is validated for the specific server model and chassis. Using non-validated memory can lead to boot failures, performance issues, or loss of vendor support.