SK Hynix 64GB DDR5-6400 PC5-51200 ECC RDIMM Server Memory — HMCG94AHBRA481N

The SK Hynix HMCG94AHBRA481N is a 64GB DDR5-6400 ECC Registered DIMM engineered for high-performance enterprise server platforms. Operating at 6400MT/s with full ECC support, this module delivers exceptional memory bandwidth and data integrity for the most demanding workloads — from large-scale virtualization to in-memory databases and AI inference. Built to SK Hynix’s rigorous server-grade standards, it is a reliable choice for data center upgrades and server refreshes.

Key Features

• 64GB capacity per module — ideal for high-density server memory configurations
• DDR5-6400 (PC5-51200) speed — industry-leading bandwidth for next-gen platforms
• ECC (Error-Correcting Code) support for data integrity and system stability
• Registered DIMM (RDIMM) design for enhanced signal integrity in multi-DIMM configurations
• 288-pin DDR5 interface — compatible with DDR5-capable server platforms
• On-Die ECC (ODECC) for additional internal error correction
• Refurbished unit — fully tested and verified to OEM specifications

Product Specifications

• Part Number: HMCG94AHBRA481N
• Manufacturer: SK Hynix
• OEM Status: OEM SK Hynix
• Capacity: 64GB
• Type: DDR5 RDIMM (Registered ECC)
• Speed: 6400MT/s (PC5-51200)
• Voltage: 1.1V
• Pin Count: 288-pin
• ECC: Yes

Memory Specifications

• Module Type: RDIMM (Registered DIMM)
• DDR Generation: DDR5
• Speed Grade: DDR5-6400 / PC5-51200
• Data Transfer Rate: 6400MT/s
• Peak Bandwidth: ~51,200 MB/s
• Ranks / Organization: 1Rx4 (Single Rank, x4)
• Die Density: 16Gb per die
• CAS Latency: CL46 (typical for DDR5-6400)
• ECC: Yes (ECC + On-Die ECC)
• Voltage: 1.1V
• Pin Count: 288-pin
• Form Factor: DIMM

Use Cases

• Enterprise server memory upgrades requiring DDR5-6400 support
• Large-scale virtualization platforms (VMware, Hyper-V, KVM)
• In-memory databases (SAP HANA, Redis, Oracle TimesTen)
• AI/ML inference servers and high-throughput compute nodes
• High-performance computing (HPC) clusters
• Data center consolidation and server refresh projects

Compatibility

• Compatible with servers supporting DDR5 RDIMM 288-pin slots
• Designed for platforms based on Intel Xeon Scalable (Sapphire Rapids / Granite Rapids) and AMD EPYC (Genoa / Turin) processors
• Verify maximum supported speed and DIMM population rules with your server’s QVL before ordering
• Not compatible with DDR4, LRDIMM-only, or consumer desktop/laptop platforms

Frequently Asked Questions

What is the difference between RDIMM and LRDIMM?

RDIMMs use a register to buffer command and address signals, supporting up to 2 DIMMs per channel in most platforms. LRDIMMs add a data buffer for higher capacity configurations but at slightly lower speeds. This module is an RDIMM.

Is this module compatible with my server?

This DDR5-6400 RDIMM is designed for servers with DDR5-capable memory slots. Please verify your server’s QVL (Qualified Vendor List) and DIMM population guidelines before ordering.

What does ECC mean?

ECC (Error-Correcting Code) memory detects and corrects single-bit memory errors in real time, preventing data corruption and system crashes — essential for server and workstation environments.

Is this a refurbished unit?

Yes. This is a refurbished SK Hynix HMCG94AHBRA481N that has been fully tested and verified to meet OEM performance and reliability specifications.

Can I mix this with other DDR5 speeds?

Mixing DDR5 speeds is generally not recommended. Most servers will downclock all modules to the lowest installed speed. For best performance, use matched modules of the same speed and capacity.

Maximize your server’s memory bandwidth with the SK Hynix HMCG94AHBRA481N — a 64GB DDR5-6400 ECC RDIMM built for enterprise-grade reliability and next-generation performance. Contact our team for bulk pricing, compatibility verification, or technical support.