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did they also make a compatible motherboard ? because I can't get mine to go past 4800Mhz when my RAM is rated for 6400Mhz with AM5 CPU. for those who hadn't done this for a while, PSA: motherboards these days have a RAM compatibility list on their product page, check it before overspending on RAM.
What goes unsaid in the article is that this will likely only work with Intel's Arrow Lake? Arrow Lake isnt being launched until next month though, so official specs are not available yet. And the full 9600 speed will very likely require overclocking. It doesnt appear Zen5 can get anywhere close those speeds.
Earlier quoted context omitted.
These are part of a new generation of DDR5 modules that add a clock driver to the module itself, rather than relying entirely on the clock signal coming all the way from the CPU's memory controller. That is expected to significantly change the game for DDR5 overclocking, and expectations based on the limitations of configurations lacking the clock drivers may not be accurate. I expect we'll see 6+ months of firmware…
I could see this maybe reducing latency, but wouldn't you still be limited by the memory bus speed regardless of how high you could clock the DDR?
The reason is there is currently a drop off in memory subsystem performance when you go above DDR5-6000 speeds on Ryzen 7x00 (and AFAIK Ryzen 9x00), because above that, the memory controller inside the chip can't run in lock-step with the memory frequency. Much of the enthusiast memory out there that is capable of higher speeds already, like say DDR5-7200, doesn't pair well with AMD chips as a result, as in that case the memory controller is forced to work at a 1:2 instead of a 1:1 ratio, introducing latency into the memory subsystem that results in overall worse performance.
On the other hand, if these CUDIMMs can hit high enough frequencies (like 10k+ MT/s,) it's possible that the benefits will outweigh the negative related to this quirk of the memory controller. Until I see this tested or someone with more expertise clarifies this point, it's hard to say. Perhaps DDR5-9600 will result in better performance than the current DDR5-6000 "sweet spot".
What goes unsaid in the article is that this will likely only work with Intel's Arrow Lake? Arrow Lake isnt being launched until next month though, so official specs are not available yet. And the full 9600 speed will very likely require overclocking. It doesnt appear Zen5 can get anywhere close those speeds.
Not an expert, but Zen 5 desktop feels like it is being held back by memory bandwidth. Several tests show there is no real benefit in >6000 DRAMs.
Earlier quoted context omitted.
More than the specific list of which RAM is compatible check the table of how many slots/GB is supported at which speed. 1x 8 GB DIMM is a lot easier to drive than 4x 48 for example. Also keep in mind a lot of it depends more on the CPU than the motherboard itself, though both play a part, and the QVL should be a "safe bet". Particularly if you're willing to throw a bit of extra voltage at the RAM. CUDIMs should help…
> 1x 8 GB DIMM is a lot easier to drive than 4x 48 for example. That's a bit of an exaggeration. What matters are DIMMs per channel , and ranks per DIMM. Consumer systems have at most two memory slots per channel, so 2x 8GB modules installed correctly is just two separate instances of one DIMM per channel, and 4x48GB is two separate instances of two DIMMs per channel, with each module being dual-rank. The best config…
The other part of 2 DIMM boards is the trace lengths can be that much shorter (they need to be the same length so fewer slots means less max length to match to).
People should be much more sceptical than they are being here. Setting the xmp profile of Hynix or Samsung memory chips is right up there with formatting usb keys way over spec. Did you know Hynix or Samsung already binned these themselves and set them to a lower spec? The number of performance memory chips I’ve had that had to be downclocked from their xmp profile for stability is ridiculous. It’s gotten to the stag…
did they also make a compatible motherboard ? because I can't get mine to go past 4800Mhz when my RAM is rated for 6400Mhz with AM5 CPU. for those who hadn't done this for a while, PSA: motherboards these days have a RAM compatibility list on their product page, check it before overspending on RAM.
That's a valuable PSA, but FYI it's been that way since the 80s. I've been bitten by compatibility issues at least once a decade since the 90s myself, and the answer from forums or support is always "did you check the compatibility table tho?".
Earlier quoted context omitted.
> 1x 8 GB DIMM is a lot easier to drive than 4x 48 for example. That's a bit of an exaggeration. What matters are DIMMs per channel , and ranks per DIMM. Consumer systems have at most two memory slots per channel, so 2x 8GB modules installed correctly is just two separate instances of one DIMM per channel, and 4x48GB is two separate instances of two DIMMs per channel, with each module being dual-rank. The best config…
> But very few motherboards restrict themselves like this for the sake of memory overclocking. Though I'd hope they'd finally start doing it considering the per DIMM capacities DDR5 brings (32 GB, with 64 GB planned), and most consumers really not going for capacities that'd require 2 DPC (DIMM per channel). 1 DPC should've been the default by now with the amount of 1 DPC and 2 DPC boards swapped, as it's just making…
From that angle I don't necessarily disagree with 4 channel boards being more common than 2 channel boards, even though I personally lean more towards a 2 channel board myself (well, depending how well CUDIMMS scale I may change my opinion).
Earlier quoted context omitted.
> But very few motherboards restrict themselves like this for the sake of memory overclocking. Though I'd hope they'd finally start doing it considering the per DIMM capacities DDR5 brings (32 GB, with 64 GB planned), and most consumers really not going for capacities that'd require 2 DPC (DIMM per channel). 1 DPC should've been the default by now with the amount of 1 DPC and 2 DPC boards swapped, as it's just making…
A lot of consumers care more about either of total capacity or the concept of "I can just double my cheap RAM later" than care about ~10% differences in RAM clock speed. The latter is for those that really know what they're doing to eek out a couple more percentage points in benchmarks or non-consumer use cases, the former appeal to both budget users and prosumers alike (just not OC enthusiasts). From that angle I do…
The thing is that this is quickly becoming impossible, even with fairly low speeds like 6000 2 DPC is not achieveable in some cases, and consumers that are buying the 4 DIMM boards aren't particularly aware of it