Server Memory Upgrades: RDIMM vs LRDIMM – Which is better?

Server Memory Upgrades: RDIMM vs LRDIMM – Which is better?
Servers and workstations tend to deal with intensive workloads that usually require high-performing memory modules with extended storage capacity. However, it is often difficult to differentiate between the right kind of server memory.
Here is a brief guide, that will help in understanding the difference between the two server memory types i.e., RDIMM and LRDIMM.
RDIMM (Registered DIMM, dual in-line memory module)
RDIMM (Registered DIMM, dual in-line memory module) with register. RDIMMs have memory bars for data transmission and add a register to it, which can be found between the CPU and memory particles, this not only ensures the effectiveness of parallel transmission but also helps with minimizing the distance of parallel transmission. RDIMM supports buffered and high-performance registered mode, making it more stable than UDIMM. This gives it the highest-capacity server RAM performance and a wide range of applications in the server RAM market. Further, expanding the capacity of RDIMMs is comparatively easier as compared to UDIMMs due to the high efficiency. RDIMMs are known to be more stable and reliable as they are capable of supporting high-performance and buffered registered mode which makes them capable of catering to intensive workloads and high-end server applications. RDIMMs with an added register is used to buffer the address and further provide the signals. This cohesive memory controller works with the register rather than communicating directly with the memory chips. this ensures that ranks per channel are higher. Moreover, RDIMMs are easier to increase in capacity and frequency than UDIMMs due to their high register efficiency. Also, this memory allows each memory channel to use three dual-rank DIMMs, it also allows partial buffering followed by an increase in power consumption and memory latency. Therefore, RDIMMs are often the best choice for servers, as the latest RDIMMs can facilitate a storage capacity of 16GB with a clock speed of 1600MHz.
LRDIMM (Load Reduced DIMMs)
LRDIMMs are comparatively less complicated than RDIMMs and use simpler register chips with an iMB (isolation Memory Buffer). This iMB buffers the address, command, and data signals. This simple buffer helps with reducing the electrical load on the system’s motherboard without impacting the performance, even slightly. The iMB ensures that electrical loading is dealt with followed by the data signals on the memory chips that are usually from the memory controller. Further, the host controllers treat iMB as the only memory chip which results in providing more slots to be filled with DIMMs including quad-ranked DIMMs. Further, LRDIMM memory is capable of changing the register chip on RDIMM memory to iMB memory isolation buffer chip. Therefore, the main benefit of LDRIMM plays an important part in reducing the memory bus load and enhancing the memory capacity.
Difference between RDIMM and LRDIMM
Choosing the right memory may seem like a complex task as it impacts the performance of the system. There are several differences that set RDIMM and LRDIMM apart and make them compatible with different systems. For instance;
RDIMMs (Registered DIMM, dual in-line memory module) are mainly used for servers as they are the high-performing memory modules that support buffered mode and consist of the registers on the chip. Further, RDIMMs support high capacity ranging up to 32GB and higher frequency that ranges up to 3200MT/s. however, due to registers, there is often a delay for longer intervals followed by an increase in power consumption. Also, these memory modules are pricier than UDIMMs.
Whereas for LRDIMMs are considered an alternative for RDIMMs but unlike RDIMMs these memory modules minimize the load and power consumption of the memory and offer maximum support capacity of the memory. However, they possess the same frequency as RDIMMs i.e., 3200MT/s but have added storage capacity that ranges up to 64GB. Further, dual-rank LRDIMM memory usually consumes around half of its power when compared to RDIMMs that require more power. Also, this memory is relatively more expensive than RDIMMs as they are also shipped in the server field.
Which One Is Better For Server Memory Upgrade
Selecting the right memory has a lot to do with the kind of usage or the system that the user owns. For instance, if the server DIMMs have a limited storage capacity of 32GB then RDIMMS but if the requirement of server architecture is more than 32GB then LRDIMM is the best yet more expensive option. Further, for optimal performance, it is preferred to add one or two RDIMMs per memory channel with two ranks per channel.
Where can I find the best server memory?
Is your server running out of storage? Memory4less.com brings you the best memory deals. Find the latest RDIMMs and LRDIMM in different variations of capacity and form factors in top brands including HP, IBM, Dell, Crucial, and more.
In case of any queries regarding server memory upgrades, you can always reach out to our memory experts through live chat or call at (800) 821-3354.
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