Samsung Unleashes a Roomy DDR4 256GB RAM

The DDR4 RAM standard sold us the idea that it would enable the possibility of creating memory modules with higher density. And today, Samsung is here to try to make good on that promise. The Korean manufacturer this week listed its 16 gigabit (Gb)-based portfolio of memory products with DDR4 memory modules up to 256GB in capacity.

To say Samsung has a little bit of something for everybody is an understatement. The company currently offers a variety of DDR4 products in the form of unbuffered DIMM (UDIMM), small outline DIMM (SODIMM), registered DIMM (RDIMM), load reduced DIMM (LRDIMM) and error correction code (ECC) UDIMM. The latest additions to the existing lineup utilize the company's 16Gb memory chips, which it produces under its own 10-nanometer manufacturing process.

On the consumer side, Samsung now offers 32GB unbuffered DDR4 memory modules. The module (M378A4G43MB1-CTD) clocks in at 2,666MHz with a CAS latency of 19 and an operating voltage of 1.2V, as specified by JEDEC. Technically, AMD's Ryzen Threadripper processors can support up to 2TB of memory. Therefore, it should be possible to run 256GB on the Threadripper platform. Unfortunately, X399 motherboards are only certified to support up to 128GB. However, the 32GB module should open the door for future motherboards with four DDR4 memory slots to house up to 128GB of memory.

Laptop users shouldn't feel left out either. Samsung also has a SODIMM variant (M471A4G43MB1-CTD) of its 32GB module with identical specifications. Mobile powerhouses such as Lenovo's ThinkPad P52 or Eurocom's Sky C line will certainly benefit from Samsung's 32GB SODIMM module.

Things get extremely interesting for Samsung's enterprise clients. The 16Gb memory chips have allowed the NAND maker to raise the capacity bar up to 256GB. No, you didn't read that wrong; we're talking about 256GB of memory on a single stick. The module is available in LRDIMM (M386ABG40M50-CYF) and RDIMM (M393ABG40M52-CYF) formats. It operates at 2,933MHz and has a CAS latency of 21 or 24 depending on the model. Despite the huge capacity and frequency, the module's operating voltage adheres to the official JEDEC specification of 1.2V. 

Although Samsung's 256GB module is clearly aimed at servers, it's likely just a matter of time before this capacity makes its way to the consumer end.

Zhiye Liu
RAM Reviewer and News Editor

Zhiye Liu is a Freelance News Writer at Tom’s Hardware US. Although he loves everything that’s hardware, he has a soft spot for CPUs, GPUs, and RAM.

  • stdragon
    "Unfortunately, X399 motherboards are only certified to support up to 128GB"
    Why is that a MB has to be "certified" to a *capacity* when what really matters is the CPU, RAM clocking and timings/latency? The only limitations that a MB should have with regards to capacity is the amount of DIMM slots available.
    Reply
  • redgarl
    Interesting, that would render Intel 3DXPOINT technology irrelevant. That is quite interesting to see that RAM is maybe still the way to go.
    Reply
  • DavidC1
    21298390 said:
    "Unfortunately, X399 motherboards are only certified to support up to 128GB"
    Why is that a MB has to be "certified" to a *capacity* when what really matters is the CPU, RAM clocking and timings/latency? The only limitations that a MB should have with regards to capacity is the amount of DIMM slots available.

    This is not the case. When the capacity gets really high, it has to make sacrifices in other areas, like performance. Getting the many chips on a DIMM to run at a certain frequency is harder than doing it with less.

    Also certification reduces headache the manufacturer has to deal with when a customer calls in and say its not compatible, and possible additional modifications the board needs to guarantee compatibility.

    Interesting, that would render Intel 3DXPOINT technology irrelevant. That is quite interesting to see that RAM is maybe still the way to go.


    Actually 3D XPoint DIMMs will be available in 128GB/256GB/512GB sizes, are nonvolatile, and cost less per GB. Plus, the total capacity of the system is going to be Intel DIMM + DRAM DIMM.

    So in case of a dual socket system with 2 DIMMs per channel using Intel DIMMs, the potential capacity is:

    DRAM = 256GB x 6 channels x 2 sockets = 3 TB
    Intel DIMM = 512GB x 6 channels x 2 sockets = 6GB
    Total = 9TB
    Reply
  • jimmysmitty
    21298390 said:
    "Unfortunately, X399 motherboards are only certified to support up to 128GB"
    Why is that a MB has to be "certified" to a *capacity* when what really matters is the CPU, RAM clocking and timings/latency? The only limitations that a MB should have with regards to capacity is the amount of DIMM slots available.

    The board has to handle the traces and power delivery. Its not just a simple run of traces from socket to slot and done.

    21298426 said:
    Interesting, that would render Intel 3DXPOINT technology irrelevant. That is quite interesting to see that RAM is maybe still the way to go.

    In no way does this even compare to 3DXPoint. This is still volatile memory. 3DXPoints whole purpose is to utilize the advantages of NAND for memory and make it non-volatile.

    This just means more capacity for high end servers.
    Reply
  • Tanyac
    If DDR5 is just around the corner (https://www.pcgamer.com/ddr5-memory-is-twice-as-fast-as...), with RAM prices as much as 3 times what they were in 2016, why would you spend anything on this DDR4?

    I get that a 2019 release probably won't translate to mainstream availability until 2021, but we're almost at the end of 2018 now.
    Reply
  • yuhong
    "Although Samsung's 256GB module is clearly aimed at servers, it's likely just a matter of time before this capacity makes its way to the consumer end."
    RDIMM and LRDIMM will probably always be Xeons etc only.
    Reply
  • Zaporro
    Ah, a live decision, would you choose to take a long to buy house of your dream and live there with loved ones? Or will you choose the 256GB ram module to bask in its glory while you live under a bridge.
    So first Samsung and every other RAM manufacturer rip off millions of customers with their collusion and price fixing scheme and now they blow all that money on useless 256GB modules that will find use at 1% of use cases...
    Reply
  • JamesSneed
    21298390 said:
    "Unfortunately, X399 motherboards are only certified to support up to 128GB"
    Why is that a MB has to be "certified" to a *capacity* when what really matters is the CPU, RAM clocking and timings/latency? The only limitations that a MB should have with regards to capacity is the amount of DIMM slots available.

    In this case and almost all cases today it is the memory controller that is the limiting factor. It may be said the motherboard only supports xx memory which is a bit misleading but very true since said motherboard usually only accepts CPU's that have memory controllers that support the same amount of memory. If the memory controller could recognize 256GB DIMM's then you would be right you could bypass the motherboard limitations but in reality the memory controllers limit is the same limit as the motherboard.
    Reply
  • JamesSneed
    21300205 said:
    Ah, a live decision, would you choose to take a long to buy house of your dream and live there with loved ones? Or will you choose the 256GB ram module to bask in its glory while you live under a bridge.
    So first Samsung and every other RAM manufacturer rip off millions of customers with their collusion and price fixing scheme and now they blow all that money on useless 256GB modules that will find use at 1% of use cases...

    My assumption is that 99% of the 256GB DIMM's will be ECC enabled sitting in high density servers in data centers. You know like Amazon AWS servers used for hosting virtual machines etc. They will sell quite a lot of these higher capacity DIMM's in the server space.
    Reply
  • danlw
    So when you die and your life flashes before your eyes, how much of it do you want to not have 256GB of RAM? JUST BUY IT!
    Reply