UCS-ML-X64G4RS-H= Cisco 64GB PC4-21300 DDR4-2666MHz ECC Registered CL19 288-Pin Load Reduced DIMM 1.2V Quad Rank Memory Module Image

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UCS-ML-X64G4RS-H= Cisco 64GB PC4-21300 DDR4-2666MHz ECC Registered CL19 288-Pin Load Reduced DIMM 1.2V Quad Rank Memory Module

  • Part Number : UCS-ML-X64G4RS-H=
  • Brand : CISCO

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CISCO UCS-ML-X64G4RS-H= Manufacturer
CISCO UCS-ML-X64G4RS-H= Form Factor
Form Factor
CISCO UCS-ML-X64G4RS-H= Capacity
CISCO UCS-ML-X64G4RS-H= Memory Speed
Memory Speed
2666 MHz
288 Pin
CISCO UCS-ML-X64G4RS-H= Interface

Full CISCO UCS-ML-X64G4RS-H= Specifications

Brand Cisco
Form Factor LRDIMM
Capacity 4GB
Memory Speed 2666 MHz
Data Integrity Check ECC
Voltage 1.2v
Rank 4Rx4
Latency Timing CL19
Pins 288 Pin
Memory Technology DDR4
Interface Type IDE

CISCO UCS-ML-X64G4RS-H= Frequently Asked Questions

What does it mean if memory runs at 1.2v?

If memory runs at 1.2V, it means that the memory module operates at a voltage of 1.2 volts. The voltage specification is an important factor in determining the power requirements and compatibility of the memory with the system.

Memory modules running at 1.2V are commonly associated with DDR4 (Double Data Rate 4) memory technology. DDR4 was introduced as the successor to DDR3 and brought significant improvements in performance, energy efficiency, and data transfer rates.

The release of 1.2V memory modules, specifically DDR4 modules, was driven by major memory manufacturers, including Samsung, Micron, SK Hynix, and others. These manufacturers recognized the need for higher memory capacities, increased speed, and improved power efficiency to meet the evolving demands of computing systems.

The shift to 1.2V voltage in DDR4 modules was motivated by the industry's focus on energy efficiency and power savings. By operating at a lower voltage, DDR4 memory modules offered reduced power consumption and heat generation compared to their predecessors.

The lower voltage of 1.2V in DDR4 modules was chosen as a balance between performance and power efficiency. It allowed for improved data transfer rates and higher memory densities while minimizing power requirements and contributing to energy-conscious computing.

DDR4 memory modules running at 1.2V voltage became the standard for mainstream computer systems, including desktops, laptops, servers, and other computing platforms. They provided higher performance, increased memory capacities, and improved power efficiency compared to previous memory technologies.

It's important to note that compatibility with the system's memory controller and motherboard is essential when using 1.2V memory modules. The system's hardware should be designed to support and operate at this voltage to ensure proper functionality.

DDR4 memory, operating at 1.2V, revolutionized the memory landscape by offering improved efficiency and performance for a wide range of computing applications. Its introduction brought significant advancements to memory technology, catering to the growing demands of modern computing systems for faster, more power-efficient memory solutions.

What does it mean if memory is DDR4?

DDR4, which stands for Double Data Rate 4th Generation, is a type of computer memory technology utilized in servers, desktops, and laptops. Its introduction occurred in 2014 as the successor to DDR3 memory.

DDR4 brought forth several crucial technological advancements compared to its predecessor:

  1. Enhanced Data Transfer Rates: DDR4 offered increased data transfer rates, facilitating faster communication between the memory and the processor. This improvement resulted in heightened system performance and responsiveness.

  2. Higher Memory Density: DDR4 introduced higher memory density, enabling more memory to be packed onto a single module. This expanded the maximum RAM capacity that could be installed in a system, accommodating larger memory requirements.

  3. Reduced Power Consumption: DDR4 memory modules operated at lower voltage levels compared to DDR3. This reduction in voltage led to decreased power consumption, thereby improving energy efficiency and prolonging battery life, especially in mobile devices.

  4. Improved Error Correction: DDR4 implemented superior error correction capabilities, enhancing the reliability and stability of the memory subsystem. This advancement was particularly critical for servers and systems that necessitate stringent data integrity.

  5. Future-Proofing: DDR4 laid the groundwork for future memory technologies and advancements. It offered scalability and compatibility with evolving processor architectures, ensuring seamless system upgrades and adaptability to future applications and technologies.

In summary, DDR4 represented a significant leap in memory technology, delivering faster speeds, larger capacities, improved power efficiency, and heightened reliability compared to its predecessors. These advancements contributed to enhanced overall system performance and addressed the escalating demands of modern computing applications.

What does it mean if memory is LRDIMM?

When memory is referred to as LRDIMM, it signifies that it belongs to the category of Load-Reduced Dual In-Line Memory Modules. LRDIMM is a specialized type of memory module that offers certain advantages over standard memory modules.

LRDIMM technology employs a memory buffer or an advanced memory buffer (AMB) chip to reduce the electrical load on the memory bus. This buffer acts as an intermediary between the memory chips and the memory controller, helping to enhance memory performance and capacity.

The main advantage of LRDIMMs is their ability to support larger memory capacities compared to standard memory modules. By reducing the electrical load on the memory controller, LRDIMMs enable the system to accommodate more memory modules per channel, thereby increasing the overall memory capacity.

LRDIMMs are commonly used in scenarios that demand extensive memory capabilities, such as enterprise-level servers, data centers, and high-performance computing environments. Their ability to support larger memory capacities is particularly beneficial for applications that involve data-intensive tasks, virtualization, and complex computations.

It's important to note that LRDIMMs require compatible hardware support. The motherboard and memory controller must specifically support LRDIMM technology. Therefore, it is crucial to verify the system's compatibility and consult the system documentation or manufacturer's guidelines before utilizing LRDIMMs.

What does it mean if memory has a speed of 2666MHz?

RAM speed is measured in megahertz (MHz) and refers to the number of cycles per second that the RAM can perform. In the context of "2666 MHz" RAM, it means that the RAM module is capable of performing 2,666 million cycles per second.

This measurement is often associated with DDR4 RAM, which is a type of Double Data Rate (DDR) RAM that was widely used in computers and servers. DDR4 RAM with a speed of 2666 MHz was released around 2014-2015. The release of DDR4 RAM marked an important advancement in technology for several reasons:

  1. Increased Data Transfer Rate: DDR4 RAM offered faster data transfer rates compared to its predecessor, DDR3. The higher MHz rating translated to improved performance in data-intensive tasks, as more data could be transferred between the RAM and the CPU in a shorter amount of time.

  2. Energy Efficiency: DDR4 RAM was designed to be more energy-efficient than DDR3. It operated at lower voltage levels, which helped reduce power consumption and heat generation. This was particularly important for laptops and servers where energy efficiency and heat management were crucial.

  3. Higher Capacity and Scalability: DDR4 RAM allowed for larger memory modules and higher capacities. This was important for applications that required a large amount of memory, such as virtualization, big data analysis, and content creation. Servers benefited from being able to accommodate more RAM for demanding workloads.

  4. Improved Bandwidth: The increased MHz rating of DDR4 RAM translated to improved memory bandwidth, which is the rate at which data can be read from or written to the RAM. This was important for tasks that involve rapid data manipulation, such as video editing and scientific simulations.

  5. Future-Proofing: DDR4 RAM's technological advancements provided a foundation for future upgrades and innovations in memory technology. This made DDR4-based systems more capable of handling evolving software and hardware demands.

Overall, the introduction of DDR4 RAM with higher speeds like 2666 MHz was important for improving overall system performance, energy efficiency, and the ability to handle more demanding tasks. As technology continued to advance, even faster RAM speeds and newer memory technologies have been developed, further pushing the boundaries of computing capabilities.


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December 22, 2022 by Scott Carpenter

"We're a Canadian company who was badly in need of a drive for our server. Wasn't sure how the cross border purchase would go but Scott and his team had us taken care of at a price that couldn't be beaten and with lightning speed and efficiency. We had our drive in just a few days. I would highly recommend this company! Wish there were more out there like them!"

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