General

Engineer's Note

This M393AAK40B41-CTC4Q is a 128GB DDR4-2400 Registered ECC RDIMM engineered for enterprise servers, delivering massive capacity scaling ideal for memory-intensive workloads such as virtualization and in-memory databases. Its octal-rank x4 configuration maximizes density per channel while the registered signal type and ECC ensure robust signal integrity and data protection under heavy load.

Technical Specs & Insights

1. 128GB capacity per module enables dense memory configurations that support hundreds of virtual machines on a single server, maximizing consolidation ratios and reducing infrastructure costs.
2. ECC protection continuously detects and corrects single-bit errors, providing the data integrity required for financial transactions, scientific computing, and mission-critical databases.
3. Registered clock and command signals stabilize signal integrity across multiple DIMMs, allowing the server to maintain reliable operation even with fully populated memory channels.
4. Octal Rank x4 organization uses deep interleaving to saturate the memory bus efficiently, sustaining high throughput under the simultaneous memory requests typical of heavily consolidated workloads.
5. 2400 MT/s transfer speed delivers a solid 19.2 GB/s peak bandwidth per channel, offering a cost-effective performance baseline for mainstream enterprise applications without exceeding thermal budgets.

Why These Specs Matter

The M393AAK40B41-CTC4Q is a server-grade DDR4-2400 RDIMM built to resolve the most critical pain points in virtualized clusters and in-memory databases. Its ECC protection continuously corrects single-bit errors before they corrupt a hypervisor’s memory space or alter a financial transaction inside a Redis cluster, directly shielding your business from silent data corruption and unexpected downtime. The registered signal buffering stabilizes the command and address lines, so you can fully populate a dual-socket server with these 128 GB modules without compromising clock integrity — essential when consolidating dozens of latency-sensitive VMs onto a single host. The octal-rank x4 organization interleaves memory accesses across eight internal rank groups, boosting effective bandwidth for real-time analytics applications where every nanosecond of query latency directly impacts user experience. Backed by a 1.2 V operating voltage, the module also lowers power consumption per gigabyte, helping dense cloud infrastructure stay within tight thermal and energy budgets while delivering the massive capacity that modern memory-hungry workloads demand.

Endurance & Reliability

General Virtualization
Deploy one 128GB RDIMM per memory channel to maximize capacity while preserving balanced memory bandwidth. In a dual-socket server with eight channels per CPU, this yields 2TB of total memory, allowing hundreds of virtual machines to run comfortably without NUMA contention. Avoid populating two of these octal-rank DIMMs per channel, as the speed may drop to 1866MHz and limit VM responsiveness.

In-Memory Database
Use a symmetrical configuration with a single 128GB module installed in every channel of each CPU socket. This ensures large dataset residency in RAM and avoids inter-socket latency penalties. For extreme capacity, a second DIMM per channel can be considered, but only if your workload tolerates reduced clock speeds; the preferred mode is one 128GB RDIMM per channel for consistent CL17 latency and high throughput.

High-Performance Computing (HPC)
Populate all memory channels with one 128GB RDIMM each to deliver the highest possible memory bandwidth per core. Octal-rank modules fully utilize the channel, so a 1DPC (one DIMM per channel) configuration sustains DDR4-2400 speed and maximizes vectorization efficiency. Pair with a CPU that natively supports 2400MHz to avoid any down-clocking, as HPC applications are extremely sensitive to memory bandwidth and latency.

Verified Compatibility

Validated compatible with Dell PowerEdge R740, R640, HPE ProLiant DL380 Gen10, Lenovo ThinkSystem SR650.

FAQ