General

Engineer's Note

As a DDR4-2400 UDIMM with ECC support, this module is engineered for entry-level servers and workstations where data integrity is critical but registered memory is not required. Its dual-rank x8 organization and unbuffered design deliver efficient interleaving and low latency for reliability-sensitive workloads like file servers and light virtualization, while the onboard ECC provides single-bit error correction to prevent data corruption in 24/7 operation.

Technical Specs & Insights

1. ECC error correction actively detects and corrects single-bit memory faults, shielding critical server data from corruption during continuous 24/7 transaction processing.
2. A generous 16GB capacity per stick maximizes memory density in limited DIMM slots, letting a single physical host comfortably run more virtual machines without bottle-necking.
3. 2400MHz clock speed delivers a stable 19.2 GB/s peak bandwidth, keeping throughput consistent when multiple enterprise workloads hit the memory channel simultaneously.
4. Dual rank x8 architecture interleaves access across internal banks, boosting command efficiency and sustaining performance under heavy multisession virtualization loads.
5. Unbuffered signal topology trims controller-to-DRAM latency overhead, giving latency-sensitive applications like in-memory databases a tangible response-time advantage.

Why These Specs Matter

Recognizing the M391A2K43BB1-CRCQ as a server-grade DDR4 ECC UDIMM, its 16GB capacity and four defining characteristics directly tackle the real-world demands of small-to-medium business servers and workstations. The first, ECC error correction, is non-negotiable for virtualized clusters and in-memory databases like Redis; a single-bit flip in a hypervisor’s memory can cascade into VM corruption or silent data loss, but ECC detects and corrects these errors instantly, preserving transaction integrity and uptime. Second, the dual-rank x8 organization interleaves memory banks, boosting sustained bandwidth under the heavy, concurrent access patterns of multiple VMs vying for resources, which prevents the performance collapse you would see with single-rank modules. Third, while it is unbuffered, this UDIMM design keeps electrical latency lower than registered alternatives, giving your SQL queries a measurable response-time advantage in latency-sensitive OLTP workloads. Finally, the 1.2V low-voltage operation reduces thermal load and power draw in a chassis running 24/7, directly lowering operational costs without sacrificing the 2400MHz data rate. Together, these attributes translate into a memory solution where data fidelity, workload throughput, and efficiency are engineered to maintain service reliability when your business depends on it.

Endurance & Reliability

Memory Type: Server Memory (DDR4 ECC UDIMM)

This is a 16GB DDR4-2400 ECC Unbuffered DIMM, suitable for entry-level servers, microservers, and workstations requiring data integrity without the capacity scale of registered memory. ECC UDIMMs balance cost and reliability in single-socket platforms. Below are capacity planning recommendations for typical server workloads.

General Virtualization
Start by populating all available memory channels with identical 16GB modules to maximize bandwidth. A typical dual-channel platform with four 16GB UDIMMs provides 64GB, comfortably supporting 15–20 lightweight VMs. Monitor memory overcommitment ratios and leave at least 20% headroom to avoid ballooning or swapping under peak load.

In-Memory Database
Prioritize capacity and latency. Use the largest supported UDIMM configuration, often 4 x 16GB for 64GB total, to hold entire datasets in RAM. Dual-rank modules like this one offer slightly better bandwidth, but ensure the CPU memory controller can handle full population at rated speed. For Redis or Memcached, 64GB is a solid entry point for moderate-sized caches.

High Performance Computing
Balance capacity with memory bandwidth. Install modules in matched sets to populate all memory channels — for a quad-channel platform, use four identical 16GB DIMMs for 64GB. This configuration enables maximum interleaving and avoids bandwidth bottlenecks in memory-bound HPC applications like computational fluid dynamics or weather modeling. Confirm the motherboard supports ECC UDIMMs at DDR4-2400 with all slots filled.

Verified Compatibility

Rigorously tested server memory, compatible with Dell PowerEdge R240, HPE ProLiant DL20 Gen10, Lenovo ThinkSystem ST50.

FAQ