RAM, or Random Access Memory, is a key component of any computer, be it a laptop, desktop,or NUC. The higher the capacity, the more data can be accessed instantly by the CPU. Each RAM stick is called a DIMM, or Dual In-line Memory Module, and UDIMMs, or Un-buffered Dual In-line Memory Modules, are themost common type of DDR5 RAMavailable today for desktop PCs. Now, a new variation called CUDIMM, or Clocked Un-buffered Dual In-line Memory Module, has emerged promising better signal integrity, faster performance, and improved reliability.
To better understand CUDIMM, it is essential to know what the differences are between DIMM, UDIMM, RDIMM, SODIMM, and CUDIMM.
DIMM/ Dual In-line Memory Module
RAM sticks, be it DDR4 or DDR5, are called DIMMs based on the fact that the pins are present on both sides of the module, as opposed to SIMM or Single In-line Memory Module. This is just the physical nature of the RAM modules and has nothing to do with capacity or performance. While both DDR4 and DDR5 RAM have 288 pins, separating the two is an offset notch that ensures DDR4 RAM cannot be connected to a DDR5 RAM slot and vice versa.
UDIMM/ Un-Buffered Dual In-line Memory Module
G.SKILL Trident Z5 RGB Series (Intel XMP 3.0) DDR5 RAM
The G.SKILL Trident Z5 RGB Series (Intel XMP 3.0) is one of the fastest high-performance DDR5 memory kits that money can buy right now. It has the best timings, and the use of SK Hynix’s latest A-die ICs means it can run at tight timings or even surpass the advertised DDR5-7200.
CORSAIR VENGEANCE RGB DDR5 6400MHz 32GB
Corsair’s Vengeance RGB DDR5 RAM kit features dual RAM modules, each having 16GB memory capacity. It has built-in XMP 3.0 profiles, offering a blend of a high-rated frequency, low latency, and a reasonable price tag in tow.For aesthetics, the RAM sticks look gorgeous as a result of the RGB LEDs on top of its dedicated aluminum heat spreaders.
TeamGroup T-Force Delta RGB DDR5 Memory
The TEAMGROUP T-Force Delta is another great RAM to pair with RTX 4060/4060 Ti GPU. It comes in two 32GB modules that provide up to 64GB of memory after installation. It also features RGB lighting support, 120-ultra-wide lighting, and support for several software for lighting effects. It supports Intel XMP 3.0 one-click overclocking and is compatible with the Intel 600 Series Chipset for the motherboard and CPU.
UDIMMs are a type of DIMM, and the most commonly used at that. Often, manufacturers don’t bother calling their RAM modules UDIMM and just call them DIMM, as the names are pretty much interchangeable at this point. Un-buffered Dual In-line Memory Modules, as the name suggests, do not have a buffer between the RAM’s memory controller and memory chips, meaning they directly interact with each other, reducing latency and leading to faster performance. But this comes at the cost of signal integrity and electrical load. This is where CUDIMMs come in.
SODIMM/ Small Outline Dual In-line Memory Module
G.SKILL Ripjaws DDR5 SO-DIMM Series DDR5 RAM 32GB
The G.SKILL Ripjaws DDR5 SO-DIMM is one of the fastest high-performance laptop DDR5 memory kits that money can buy right now. It offers lower latency than many of its peers thanks to the use of screened IC chips as well as G.SKILL’s selective binning process.
CORSAIR Vengeance SODIMM 4800MHz DDR5 RAM 32GB CL40
Not all computing devices can fit the standard length of RAM sticks. Laptops and small-form factor PCs are often struck with space limitations and SODIMMs are the solution. They are essentially UDIMMs, but much smaller, at around half the length. The smaller size does not deter SODIMMs from using the same technologies as their larger counterparts. At the same frequencies, SODIMMs will perform identically to standard UDIMMs.
RDIMM/ Registered Dual In-line Memory Module
RDIMMs come with two register chips built into the stick that act as a buffer between the controller and chip. The register identifies the correct location for the data that has been requested from the CPU. This offloads the work from the chipset, reducing electrical load and also avoids errors during data transfers. This makes RDIMM more stable and reliable than standard UDIMM and is therefore used in servers and workstations. Despite their relatively higher latency, they are more expensive than UDIMMs, but considering the use case, the lowest latency isn’t really a requirement.
RDIMMs mostly come with ECC or Error Correcting Code, which is an extra chip that detects and corrects data corruption during data transfers.
CUDIMM/ Clocked Un-Buffered Dual In-line Memory Module
As fast and responsive as DDR5 RAM is, there are some issues the technology needs to overcome to become even faster. One of the major issues is signal integrity, which is why DDR5 DIMMs, or UDIMMs, can’t perform faster than the currently available DDR5 modules. Considering the wide range of capacity and performance combinations available on the market, there are some electrical challenges that need to be overcome in order for DDR5 memory, and possibly DDR6, to become even faster. CUDIMM is seemingly the solution to that as it promises better signal integrity, leading to improved stability and higher operating frequencies.
G.SKILL Trident Z5 CK 48GB
The G.SKILL Trident Z5 CK 48GB is the latest iteration of DDR5 UDIMMs that boast speeds of up to 9600 MT/s. The kit includes two 24GB modules with CAS Latency of 46 and timings of 46-58-58-153. The modules operate at 1.45V and come with support for Intel XMP 3.0.
CUDIMMs are newer versions of UDIMMs that come with a clock driver (CKD) right on the DIMM. This integrated circuit (IC) regenerates the clock signal driving the chips. This means the DIMM does not have to directly use the clock from the CPU, but can instead rely on a clean locally generated clock. This leads to increased stability at higher speeds thanks to the reduced load on the chip.
This also means DDR5 CUDIMMs will be able to achieve higher clock speeds and frequencies without any changes to the connector, so both manufacturers and users will be able to make a smooth transition.
CUDIMM: Where Does It Stand Today?
At Computex, a few memory vendors showcased their CUDIMM products, and some of them are closer to bringing those kits to the market. Colorful recently showed its overclocked CUDIMM kit that was able to reach 9600 MT/s with a CAS latency of 44. However, the Colorful iGame team was able to push the kit further and hit 10,000 MT/s with 24GB modules in dual-channel. These modules have an XMP specification of 9600 C44 at 1.5V and 9200 C46 at 1.45V.
Even though the team was able to hit 10,000 MT/s, casual users may not be able to hit that peak with their setups. That being said, speeds ranging between 6400 MT/s and 9600 MT/s will be much easier to hit.
Kingston has also teased its CUDIMM DDR5 kit called Fury Renegade, which includes two 24GB sticks that can hit 8200 MT/s and CL40 timings.
Meanwhile, G.SKILL is also working on its Trident Z5 CK kit that boasts 9600 MT/s and for now, they are the only oneslisted on Neweggwith an ETA of November 1.
FAQ
Q: What is a CUDIMM?
CUDIMM stands for Clocked Unbuffered Dual In-line Memory Module, and it is the latest variation of DDR5 memory kits that are more stable and faster than currently available kits.
Q: Is UDIMM the same as DIMM?
UDIMM or Unbuffered DIMM is a type of Dual In-line Memory Module (DIMM). DIMMs are memory sticks that have pins on both sides resulting in 288 total pins. The terms UDIMM and DIMM are often used interchangeably.
