Ryzen 9 9950X with 4×32GB RAM

[A Computer Guy]

Yeah, but so far those boards I hoping for are not existing,
Also QVL just means they checked that parts together, and it worked.
I've used other parts, that is only a risk - but also DDR5 is standard - and all parts should conform to the standard ...

The main reason is
Video editing (memory size) and encoding (memory speed) is important

Sadly no, that would be the easy way.

Does Ryzen platform fit your use case then? Threadripper might be better for the task although it costs a lot more and even more on top of that for the current gen.

Most likely I will get the Zen5 9950X, which has dual channel memory controller (wish I could afford the 7960X for the sweet 4 channel MC).

I found an interesting combo listing on ebay Threadripper 3970X (32c/64t)- ASrock TRX40D8-2N2T Motherboard - 256GB 2666Mhz for EUR 1,499 (a little bit more than a only a new 7960x)
Have no idea if that meets your needs. There is a cheaper listing for only EUR 1,249.00 (same thing but only 128GB ram). It's possible 9950x might completely run circles around 3970X.

 

[Assimilator]

Yeah, but so far those boards I hoping for are not existing,
Also QVL just means they checked that parts together, and it worked.
I've used other parts, that is only a risk - but also DDR5 is standard - and all parts should conform to the standard ...

The JEDEC DDR5 specification defines multiple speeds, starting at 3200MHz. It does not define how those speeds relate to number of physical DIMMs involved, nor what speeds implementers must support. A Zen 5/X670E platform that supports 4x DDR5-3600 DIMMs is as compliant with the specification as an Intel 14th gen/Z790 platform that supports 4x DDR5-4800.

The main reason is
Video editing (memory size) and encoding (memory speed) is important

Memory capacity is going to be far, far more important than bandwidth for this use-case. But if bandwidth is a concern then your only real option is to jump to Threadripper which has more memory channels and that gets real pricey real fast, even if you're buying old second-hand stock.

It's possible 9950x might completely run circles around 3970X.

It will entirely depend on the task. TR 3000-series is only Zen 2, but it does have at least 4 memory channels compared to the mainstream of 2 (3990X and 3995WX have 8 channels).

 

[gurusmi]

QVLs are for wimps.

The big question here is whether the lower memory speed makes a noticeable difference for your applications. Most applications do not show major differences. A good way to test your applications before purchase of memory is to underclock your existing memory and see whether that makes a difference for your workload. If it doesn't then higher speed is likely useless.

Wrong. before thinking of getting 2 or 4 modules one should check if four modules need different voltages. I.e. Asus needs lower voltages if four modules are n use. If one doesn't read careflly the QVL he don't know about that fact. He buys four bars of 1,45V ram and wonder why he cannot run that bars. My board (Asus ProArt X670E-CREATOR WIFI) delivers only 1,35V with 4 DDR5 bars. :O

I would suggest the TS to read the qvl first. Then he has the technical data for using 2 and 4 bars of ram. After that he can search for similar ram bars of his choice. Everything else is braindead.

 

[Dr. Dro]

It will entirely depend on the task. TR 3000-series is only Zen 2, but it does have at least 4 memory channels compared to the mainstream of 2 (3990X and 3995WX have 8 channels).

This is true, however, Raptor Lake still tends to match or outperform quad-channel DDR4 platforms on this department, perhaps not the Zen 2 rippers, but definitely the original Zen/Zen+ ones or Intel Sky/Cascade Lake-X. I wonder if you can run a 2x48 GB configuration on a board like the Apex or Tachyon, at 6400-6800ish, at 6400 a Raptor Lake will have around ~92 GB/s of memory bandwidth, at 7600 i'm currently pulling around 118 GB/s on Aida tests. There's only one review of a 2x48 kit on TPU and @ir_cow got 6800 on the Apex, doing about 100 GB/s

Neo Forza MK5 DDR5-6000 96 GB CL40 Review

Neo Forza is ready with more DDR5 options, unveiling the DDR5-6000 MK5 96 GB (2x 48 GB) high-capacity memory kit priced at a highly competitive $263. Thanks to support for both Intel XMP and AMD EXPO, this memory will run great on all platforms.

www.techpowerup.com

In any case, such a system is not exactly affordable

 

[csendesmark]

Does Ryzen platform fit your use case then? Threadripper might be better for the task although it costs a lot more and even more on top of that for the current gen.


I found an interesting combo listing on ebay Threadripper 3970X (32c/64t)- ASrock TRX40D8-2N2T Motherboard - 256GB 2666Mhz for EUR 1,499 (a little bit more than a only a new 7960x)
Have no idea if that meets your needs. There is a cheaper listing for only EUR 1,249.00 (same thing but only 128GB ram). It's possible 9950x might completely run circles around 3970X.

Originally I wanted to start the thread with crying about how expensive the Threadripper is...
Then I decided not to start with complaining
If I had 4500€ to get the parts, I would not bother you with the R9 9950X route

Memory capacity is going to be far, far more important than bandwidth for this use-case. But if bandwidth is a concern then your only real option is to jump to Threadripper which has more memory channels and that gets real pricey real fast, even if you're buying old second-hand stock.

96GB is a acceptable trade between size and speed (6600~6800)

It will entirely depend on the task. TR 3000-series is only Zen 2

I would not spend money on EOL tech, even if it's a "new" cpu and mobo, a many things can go wrong, and then I stuck with that.

 

[igormp]

I'm on a similar boat, looking to upgrade from my 5950x with 128gb of ram to a 9950x, but ideally with 256gb of ram. FWIW, 64GB from kingston won't be a thing until next year, sadly.

If you really value frequencies, go for 2x48GB, you should be able to manage 6000MHz+ with those, just check the QVL to be sure.

With 4x32GB you'll be lucky to even reach anything past 5200MHz. 4x48GB seem to clock a little better, with some folks managing 5200~5600MHz, and some even doing 6000MHz with lots of manual tuning. There's a thread on the neighboring forum about such high RAM setups with some interesting experiences:

DDR5 4 dimms on am5 -- what's working, what's not?

Are you running 4 dimms on the AM5 platform? What about LGA1700? Post a pic and details of your setup! Background I’ve been testing the new VSOC/agesa changes from AMD and 48gb dimm support. I am happy to report 96gb @ DDR5-6000 (2x48gb) is working great! I’ll have a video about that soon...

forum.level1techs.com

If you're not in a hurry, maybe you could wait for those 64GB UDIMMs to become a thing, otherwise 2x48GB seems like your best bet.

 

[ir_cow]

I actually don't know the limit of dual-rank on AMD, but 6000-6200 MT/s works and thats what matters.

For Intel 13th/14th gen it going to be in the 6800-7000 range.

Unless you absolutely need more than 96GB, I would just stick with that size and get DDR5-6000 and be happy it works without much hassle.

Just so people are aware, it doesn't matter if it's 2x32 or 2x48. Still dual-rank memory. The hard memory speed limits will be the same.

 

[csendesmark]

I actually don't know the limit of dual-rank on AMD, but 6000-6200 MT/s works and thats what matters.

For Intel 13th/14th gen it going to be in the 6800-7000 range.

Unless you absolutely need more than 96GB, I would just stick with that size and get DDR5-6000 and be happy it works without much hassle.

Just so people are aware, it doesn't matter if it's 2x32 or 2x48. Still dual-rank memory. The hard memory speed limits will be the same.

Actually we know, thanks for Zach

https://www.amd.com/en/products/processors/desktops/ryzen/9000-series/amd-ryzen-9-9950x.html

For 2 memory module
2x1R DDR5-5600 MT/s
2x2R DDR5-5600 MT/s
So no difference with double rank memories.

On the Intel option,
Nah... I am not fanboy for any of the companies, but Intel is no bueno as of now, they need to give me the stuff a lot cheaper before I dare to spend money on their stuff...

If you really value frequencies, go for 2x48GB, you should be able to manage 6000MHz+ with those, just check the QVL to be sure.

Thanks for the good info.
Unlikely that I will wait till the 64GB modules, maybe I upgrade later from 2×48 to 2×64.

 

[mkppo]

I'd say get 2x48GB, and you can always upgrade later when you really need more than 96GB and are prepared to take a performance hit. Maybe by then the AGESA updates will improve speeds for 4 sticks, who knows.

 

[ir_cow]

For 2 memory module
2x1R DDR5-5600 MT/s
2x2R DDR5-5600 MT/s
So no difference with double rank memories.

Until you go with 4 DIMMS and officially AMD only supports DDR5-3600.

4x1R DDR5-3600
4x2R DDR5-3600

 

[csendesmark]

Until you go with 4 DIMMS and officially AMD only supports DDR5-3600.

4x1R DDR5-3600
4x2R DDR5-3600

Yeah, we already agreed on it is 2×48 the way it is, since the 64 GB modules are not even in the corner yet.

 

[kapone32]

It is too bad bad that high density DDR5 RAM are so expensive. Expensive enough to be something you only use if you need it. I like the TeaM 6000 mt/s RAM 32GB modules when they are $129 CAD. I think it is unfair to pay $250+ CAD for higher density sticks and the timings suck at that price too.

 

[Lewzke]

2x32 is enough for most of the work tasks, except some AI training but that needs also tons of VRAM.

 

[JWNoctis]

96GB is a acceptable trade between size and speed (6600~6800)

No one seemed to have mentioned how desktop Zen 4/5 CPUs are bottlenecked by the IF on absolute memory bandwidth. Competitor offerings are somewhat better in that respect, though currently suffering from other problems that might be exacerbated by high memory bandwidth usage.

6600-6800MT/s on the memory bus offers only marginal advantage over 6000-6400MT/s anyway, even if you could stabilize 2200MHz FCLK. I have not seen much example of anyone pushing 2266MHz in daily use.

 

[ir_cow]

Start to fiddle with FCLK and you could run into stability issues. Leave alone if using the computer for work.

 

[Sarajiel]

96GB is a acceptable trade between size and speed (6600~6800)

As others mentioned before, the realistic expectation for any R9 7950X or R9 9950X would be DDR5-6000 for 2x48GB. DRR5-6200 means you are lucky with your CPU's memory controller, and DDR5-6400 is pretty much winning the silicon lottery. I've seen some people posting ZenTimings screenshots of DDR5-6600 at some extreme overclocking sites, but w/o an intensive stress test, I've got my doubts.
Usually, you want to run MCLK:FCLK:UCLK in a 3:2:3 ratio for the lowest latency when going for 6000MT/s to 6400 MT/s. Slight FCLK overclocks, anything between 2000MHz and 2200MHz, should be fine as long as Vsoc is reasonable (1.15V - 1.2V), since the infinity fabric uses error correction and re-transmissions. There are a couple of ways to test fabric stability, and it seems the most popular way is to play music in the background while hammering their CPU's memory controller while stress testing with something like linpack.

Alternatively, you could try to run DDR5-8000, at a 2:1:1 ratio, but that means you need a good and quite expensive memory kit with 24Gb Hynix ICs, and a motherboard on an 8-layer PCB that ideally only comes with two DIMM slots to get there without much trouble. From what I've seen so far, R9 9950X is still a pain when it comes to DDR5-8000 on 4 DIMM slot boards, but unlike the 7950X, it might get there eventually according to AMD.
Keep in mind that DDR5-8000 should actually benefit much more on dual-CCD chips while running heavy workloads than what most folks test these setups for. A 7800X3D won't see much improvement in gaming, since it only has a single fabric link, compared to the two of a R9 9950X.

From my own experience, I run a couple of R9 7950Xs and R9 7950X3Ds, mostly with 96GB of DDR5-6200 actively cooled at manually tuned timings. Usually a 80mm or 92mm cooler strapped onto the back of the GPU is fine, but if you want a nicer look, you can get a Jonsbo NF-1 as well. All sticks are either Kingston or G.Skill and use 24Gb Hynix M-die. Everything is stress tested for about a week running a mix of FurMark plus a collection of the usual memory intensive workloads, e.g. Prime95 (large FFTs), y-cruncher N63 & VT3, linpack Xtreme, GSAT via WSL2, etc.
One 7950X boots DDR5-6400 easily, but it's sadly not stable. Another one won't even post at that speed... aka silicon lottery.

For 128GB, I was able to run DDR5-5600 on a B650E Aorus Master on XMP/EXPO profile #2 with two pairs of Kingston DDR5-6000 CL36 kits out of the box. Those kits are Hynix A-die and easily clock to DDR5-6200 as well. Since that is my main editing machine (DaVinci Resolve, Twinmotion, UE4 & UE5), I switched them out for 96GB for the faster speed. However, with a current AGESA, it should be possible to run those 4x 32GB sticks at a 4:3:4 ratio, which should give them a bit more throughput due to the slight FCLK overclock without increasing latency. Right now, I'm waiting for another 8-layer PCB motherboard to try the 128GB setup in one of my render nodes, where memory speed isn't that important, but I'm still curious about silicon variance of the same type of AMD CPU.
Maybe I'm just lucky and got some golden memory sticks, but 128GB seems to be possible at 4800MT/s out of the box on even a 6-layer PCB board like my MSI B650 Carbon WiFi with a mediocre CPU.

The general problem with quad-rank or 4 DIMM setups is heat dissipation. Those above-mentioned Fury Beast sticks come with thin heat spreaders that allow just enough air circulation between them. My 48GB Fury Renegade sticks come with thicker heat spreaders and almost touch each other in the 192GB config. My G.Skill Ripjaws S5 kits are better in that regard, but none of my boards like their XMP profile and the PMIC lacks a thermal pad, which means that those sticks require a very high tRFC of ~190ns compared to the ~160ns of the Kingston kits to avoid overheating.
If you don't manually tune your memory, you can just use XMP/EXPO profiles and set a longer refresh interval with a shorter refresh cycle as the easiest way to noticeably overclock DDR5. However, you should still stress test it, like any other overclock.

 

[Princess Garnet]

I'm going to echo a lot of what others have said about going with two DIMMs, and specifically 2 x48 GB being your best compromise.

I'm possibly going to soon be in the same situation (whether I move to AM5 sooner or wait depends on pricing and performance of the 9800X3D, but Zen 5 ended up being slightly under-impressive to me so I may wait, as I'm on a 5800X3D now so there's no real rush to upgrade anyway), and my pre-research has led me to believe two DIMMs would be my best compromise. I've traditionally gotten a lot of RAM, meaning I've ended up with four DIMMs for a given platform, but I've basically conceded that if I move to AM5 soon, I'd probably be going with two DIMMs. Which isn't a problem, because I don't care about the DIMM count itself (I'd rather have less if anything) but rather the capacity.

Mid-2000s: 4x 256 (1 GB) MB DDR 400 MHz (socket 478)
2008/2009: 4x 2 GB (8 GB) DDR2 800 MHz (LGA 775)
2011: 4x 4 GB (16 GB) DDR3 1,600 MHz (LGA 1155)
2020: 4x 16 GB (64 GB) DDR4 3,600 MHz (AM4)

All of those "just worked". The DDR2 configuration was even started as two DIMMs (2008) and had two of the "same" DIMMs added later (2009) and that also worked just fine like that (the latter DDR3 and DDR4 configurations were purchased as kits of four from the start). The latter two configurations were dual rank, but I'm not positive on the DDR2 configuration. Maybe someone who knows more can guess based on the year/capacity (it was Corsair XM2s RAM). The DDR(1) configuration was likely single rank. It was low capacity for the time and some no-name stuff in an OEM. But all of it "just worked" and those speeds would have been about whatever was "sweet spot" at the time.

However, even with the DDR4 configuration I have now, during some of my stability issues, I've had to question if my heavy memory configuration is involved. Stabilizing RAM configurations is even harder with DDR5, and daisy chain motherboards seem to be pretty much everything now (I wish t-topology was still around for some motherboards for those of us wanting "RAM sweet spot with more capacity" as opposed to "frequency to the moon", but maybe even t-topology wouldn't help us reach that which is why they aren't around?).

So if I wanted to move to DDR5 and go up in capacity, I'd basically have to be looking at 2x 48 GB, which is still dual rank but only two DIMMs and seemingly has a good chance at 6,000 MHz on AM5 from what I've found. With four DIMMs, even if it's only single rank, that's apparently a bit tougher to achieve, and I've only very rarely seen 6,000 MHz+ on four DIMMs accomplished with DDR5 (and more often it seems to be on LGA 1700 when it is accomplished, where 6,000 MHz itself is still a concession compared to what it typically achieves so...). This is like the very early DDR4 on AM4 days again where anything above two, dual rank DIMMs is increasingly questionable if it will work at sweet spot speeds. Once you get into four DIMMs on DDR5 and especially with AM5, it seems concessions to (in AM5's case) 5,200 MHz to maybe 5,600 MHz if you're lucky, are what you should expect from my attempt to research this.

 

[JWNoctis]

I'm going to echo a lot of what others have said about going with two DIMMs, and specifically 2 x48 GB being your best compromise.

I'm possibly going to soon be in the same situation (whether I move to AM5 sooner or wait depends on pricing and performance of the 9800X3D, but Zen 5 ended up being slightly under-impressive to me so I may wait, as I'm on a 5800X3D now so there's no real rush to upgrade anyway), and my pre-research has led me to believe two DIMMs would be my best compromise. I've traditionally gotten a lot of RAM, meaning I've ended up with four DIMMs for a given platform, but I've basically conceded that if I move to AM5 soon, I'd probably be going with two DIMMs. Which isn't a problem, because I don't care about the DIMM count itself (I'd rather have less if anything) but rather the capacity.

Mid-2000s: 4x 256 (1 GB) MB DDR 400 MHz (socket 478)
2008/2009: 4x 2 GB (8 GB) DDR2 800 MHz (LGA 775)
2011: 4x 4 GB (16 GB) DDR3 1,600 MHz (LGA 1155)
2020: 4x 16 GB (64 GB) DDR4 3,600 MHz (AM4)

All of those "just worked". The DDR2 configuration was even started as two DIMMs (2008) and had two of the "same" DIMMs added later (2009) and that also worked just fine like that (the latter DDR3 and DDR4 configurations were purchased as kits of four from the start). The latter two configurations were dual rank, but I'm not positive on the DDR2 configuration. Maybe someone who knows more can guess based on the year/capacity (it was Corsair XM2s RAM). The DDR(1) configuration was likely single rank. It was low capacity for the time and some no-name stuff in an OEM. But all of it "just worked" and those speeds would have been about whatever was "sweet spot" at the time.

However, even with the DDR4 configuration I have now, during some of my stability issues, I've had to question if my heavy memory configuration is involved. Stabilizing RAM configurations is even harder with DDR5, and daisy chain motherboards seem to be pretty much everything now (I wish t-topology was still around for some motherboards for those of us wanting "RAM sweet spot with more capacity" as opposed to "frequency to the moon", but maybe even t-topology wouldn't help us reach that which is why they aren't around?).

So if I wanted to move to DDR5 and go up in capacity, I'd basically have to be looking at 2x 48 GB, which is still dual rank but only two DIMMs and seemingly has a good chance at 6,000 MHz on AM5 from what I've found. With four DIMMs, even if it's only single rank, that's apparently a bit tougher to achieve, and I've only very rarely seen 6,000 MHz+ on four DIMMs accomplished with DDR5 (and more often it seems to be on LGA 1700 when it is accomplished, where 6,000 MHz itself is still a concession compared to what it typically achieves so...). This is like the very early DDR4 on AM4 days again where anything above two, dual rank DIMMs is increasingly questionable if it will work at sweet spot speeds. Once you get into four DIMMs on DDR5 and especially with AM5, it seems concessions to (in AM5's case) 5,200 MHz to maybe 5,600 MHz if you're lucky, are what you should expect from my attempt to research this.

Again, I'd say 32Gb chips/64GB modules cannot come quickly enough. I do recall how it was once said that 128GB or even larger modules would be a theoretical possibility, when DDR5 was new.

As to topology, I could only assume that being able to claim "7200+" memory overclock capability on a value motherboard has taken priority. Even on AM5.

I could confirm that 2x48GB at 6000MHz should(n=1 plus hearsay) more or less work. The kits are currently supposed to be invariably 24Gb Hynix M, and goes for about as much as a new 7800X3D. I've seen one example of someone stabilizing 4x32GB at 6000C30 sufficiently to at least log a screenshot.

Though I guess 128GB, or 192GB, or even 256GB RAM would not be substantially much superior to 96GB for most desktop use case, and gets rather expensive fast.

 

[Assimilator]

Though I guess 128GB, or 192GB, or even 256GB RAM would not be substantially much superior to 96GB for most desktop use case, and gets rather expensive fast.

This is one of the reasons why I downgraded (sidegraded?) from a Zen 3 5900X to a Zen 2 3960X, instead of jumping on the Zen 4 train: DDR4 is so cheap that the guy I bought my Threadripper setup from was basically giving away the 128GB that came with it. Do I need that much RAM? No. Is it fun to run a y-cruncher pass for 10 billion digits of pi, while continuing to use the system for everything else I do daily? Yes.

 

[Sarajiel]

I do recall how it was once said that 128GB or even larger modules would be a theoretical possibility, when DDR5 was new.

From what I remember, the initial revision of the JEDEC DDR5 standard already included 64Gb memory chips, aka 128GB unbuffered sticks. If required, the JEDEC consortium could again add additional specifications like higher speed bins or chip densities as needed. However, this probably depends on how fast the DDR6 standard will be finished and implemented, and of course how many teething problems the chip manufacturers have. Micron is already at DDR5 D-die, and they still have trouble manufacturing ICs that go beyond the 6400MT/s speed bin.

 

[ir_cow]

Didn't we have a teaser at the end of 2023 of 8800 JEDEC 512GB? Of course that is only server stuff. With prices the way they are 4GB ICs will be through the roof.

 

[unwind-protect]

Just as a datapoint, I have been using 4 sticks of RAM in all my computers with unbuffer DIMMs for at least 20 years. For me that always worked fine, although I often mix RAM brands and generally stuff random DIMMs in. And the performance doesn't seem to affect the applications I spend CPU time on.

 

[jxdking]

I'm on a similar boat, looking to upgrade from my 5950x with 128gb of ram to a 9950x, but ideally with 256gb of ram. FWIW, 64GB from kingston won't be a thing until next year, sadly.

Yep.
DDR5 comes with much higher latency. It has to run above 5600 to get meaningful advantage comparing to DDR4. That means you are limited to only 2 dimms populated. 128GB with DDR4 are better suited.

 

[igormp]

Yep.
DDR5 comes with much higher latency. It has to run above 5600 to get meaningful advantage comparing to DDR4. That means you are limited to only 2 dimms populated. 128GB with DDR4 are better suited.

Luckily my workloads are not really dependent on latency, quantity is way more important, so the higher DDR5 latencies become irrelevant as long as I can double the amount of RAM I have (along with the way faster CPU).
I'd be fine with 5000~5600MHz, whatever works out of the box with XMP/EXPO without me needing to fiddle with anything.

 

[jxdking]

Luckily my workloads are not really dependent on latency, quantity is way more important, so the higher DDR5 latencies become irrelevant as long as I can double the amount of RAM I have (along with the way faster CPU).
I'd be fine with 5000~5600MHz, whatever works out of the box with XMP/EXPO without me needing to fiddle with anything.

Based on AMD's specs, if you populate 4 dimms, it only supports 3600MT/s