Is 128GB of DDR5 IMPOSSIBLE on AM5? Level1 Investigates!

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[@ActuallyHardcoreOverclocking]

AIDA's memory test has a tendency to hit the L3 cache during the "RAM tests" Also you can literally calculate max memory bandwidth. DDR5-4000 has a max bandwidth of 64GB/s. DDR5-6000 can't do more than 96GB/s

[@Level1Techs]

Yes, I should have mentioned that.

[@TheSlickmicks]

Buildzoid , I love it when you drop in with some fresh knowledge nuggets on other vids.

[@frzen]

I'm still interested in how to get 2T command mode on am5 I can only get 2T GDM off at 3600CL30 but at 4600CL40 (my pb completely stable) its 1T with GDM on. I thought uneven secondary timings was the answer but it didn't work. Asus support didn't say whether it could be added to the BIOS when I asked

[@dgo4490]

Well, a memory benchmark should be designed large enough to mitigate that. Could it be more like "intel has aida memory test optimizations in its prefetchers"? They do have a tendency to design for popular synthetics, where amd designs of real world use.

[@ActuallyHardcoreOverclocking]

@@dgo4490 actually right now AIDA is most inaccurate on AMD. The infinity fabric at 2GHz should have a max bandwidth of 64GB/s.

[@marcogenovesi8570]

Amazing, now server-grade boot times are a reality for desktop.

[@myselfremade]

I mean, slow booting has always been an option

[@TommyApel]

for the first time in decades IBM now has competition for 1st place as the slowest systems to boot..... "great"

[@Aegor1998]

@@TommyApel I thought their petite boot was supposed to be comparable fast? At least that is what I heard for the Power 9 platform, and I would expect it is the same or better for newer ones.

[@marcogenovesi8570]

@@myselfremade 5 to 10 minutes? That's Windows-XP-on-a-Dell levels of slow booting

[@TommyApel]

@@Aegor1998 not really, IBX ThinkServers are by a long mile the slowest servers to boot that I've ever had the displeasure of working with, it was at the point where you started looking for your car keys to go to the datacenter before they came back online, next after those is HP which are also ungodly slow to get through post especially if you have raid controllers.

[@sudpud]

GLAD someone is talking about this! There are a lot people wondering why their 4 slot memory config can't run DDR5-6000 on AM5.

[@ChatGTA345]

And not just for AMD!

[@NetrunnerAT]

AM4 do the Same. Its normal.

[@ChatGTA345]

@@NetrunnerAT That said 128GB 3600 DDR4 was running very well, unlike the new DDR5-6000 "sweet spot"

[@NetrunnerAT]

@@ChatGTA345 AM4 do the Same. I use 4000 128gb Kits and with two Sticks i get this Speed, But If i use 4 i get only 3400. This is normal ... Nothing new 🤷

[@ChatGTA345]

@@NetrunnerAT Yeah I'm not arguing, just noting that I ran 3600 with AM4 and that was rock solid and top-tier performance, unlike with AM5 or Z790.

[@bjn714]

3:00 I've experienced this on countless DDR4 boards in the last few years, _especially_ in the ITX space. Have to not only push down, but help it in place by pushing the latch closed.

[@jmwintenn]

same. went small board this time and had to reseat the ram because it wouldnt post even though it "clicked."

[@derekp6636]

i HATE it ... makes me feel like i'm going to break the board/chip and I double check the orientation at least 3 times

[@bjn714]

@@derekp6636 Yeah the crunching sounds of the slot is always unsettling, and I build 8 or so systems a month. Unfortunately getting them backward is still a problem, since it's fairly easy to miss which way the key is oriented if you're not careful, and given how close the key position is between DDR4 and DDR5, it's also easy to think you've got the correct type of RAM when you may not, as well, so even more care is needed. I know they didn't really have room to move the key very far, but it would have been nice if DDR5 did differ a little more vs DDR4 in connector appearance. Would have saved one client who brought an in-progress build to me, since they tried shoving DDR4 into a DDR5 board and ruined the board. Luckily the RAM was undamaged.

[@myselfremade]

@@bjn714 they REALLY should have gone to double key DIMMs. One in the middle, and one close to one end.

[@bjn714]

@@myselfremade yeah, would be nice, but they'd have to divide the data bus segments to do so, and for signal integrity reasons this was not done. A new PCB design that was either longer or shorter would have been the true ideal, solution, but alas, $ talks, so here we are.

[@MaheerKibria]

Gskill's SKU makes sense and instantly tells you a lot about the product. F5 means DDR5, 6000 is the rated speed. 3040 is the first two cas latencies of 30 and 40 32gx2 tells me that it is 2 stick of 32 GB stick Tz5n means it is trident z with Expo profieles where as TZ5 whithout N means it is XMP profiles. The lack of a K or S means it only comes in one color way

[@Sebyllis7350k]

Jesus Christ why do I need to know that in the SKU name? Should AMD rename their 7950x to 7950x16 in order to tell you that it has 16 cores? If the product name can tell you what chip the ram is actually using, that would be much appreciated because Amazon or Newegg pages pretty much never state that.

[@fistan5447]

@@Sebyllis7350k that is too much information to shorten further. And every bit is relevant. If you only care about the speed and capacity, just search for those. For guys like me, knowing that actually helps alot. I'll always remember what Maheer said now.

[@SafyreWorks]

@@fistan5447 Agreed! One string to rule them all. Thank you @MaheerKibria!

[@mattshortland]

Running a VFIO setup on Ryzen 7000 with the iGPU as my linux display out and 128GB. 4200 stable is the most I can get with my RAM (corsair non EXPO kit). The newest UEFI really helped stability with my MSI board. There's a long way to go. Thanks for putting in the work Wendall, keep fighting the good fight!

[@СусаннаСергеевна]

Have you tried passing the iGPU through? I've been trying since I got my processor and gotten absolutely nowhere.

[@TheGreatSpiff]

@@СусаннаСергеевна I haven't tried it myself, but I believe this is down to IOMMU groups, is it not? Curious what chipset you are running? I have heard that the 650 boards have awful iommu grouping that makes it impossible.

[@СусаннаСергеевна]

@@TheGreatSpiff X670E ProArt. The IOMMU groups are actually great, everything I can imagine wanting to split apart is split apart. The iGPU is in an IOMMU group it shares with some audio device I'm assuming is HDMI audio. As it is I can boot a VM and detect the iGPU as an AMD GPU, but the driver refuses to bind to it no matter what I do.

[@Soras_]

has difficulty hitting 4800？ add voltage to mc to see if that help.

[@mattshortland]

@@СусаннаСергеевна no I have not

[@Alkaris]

They really should reinforce the RAM slots and make it so RAM sticks can properly insert themselves into the slot without having some janky thing where it doesn't fully click into place. When inserting RAM you're putting a lot of pressure on the slot and RAM sticks, which feels like it's gonna break.

[@Yuzuki1337]

Even on generations before, inserting RAM could be feeling pretty sketchy sometimes - so hearing this about DDR5 has me a little worried lol. But I'm sure manufacturers will figure it out sooner or later, just how they'll have to figure out more resilient PCIe slots.

[@creed5248]

Yeah - Probably not a good idea to reseat them when the motherboard is in the case on the standoffs ...

[@W1ldSm1le]

Boards are wildly more expensive and more cheaply made what a joke

[@1991shadowheart]

Good thing I bought a single dual stick kit of 64gb 6000mhz for my steel legend, as opposed to two. Phew. Thank you Wendell, answering a burning question I've had for the last few days. ❤️

[@Bayonet1809]

I'm hoping that Zen 4 with 3D cache will, as the 5800X3D did, ameliorate the performance impact of slower memory, and thus allow for highly performant quad rank setups.

[@abavariannormiepleb9470]

If AMD isn‘t releasing a 16-core 3D SKU this time around I‘ll be pretty pissed myself. Remember that 5900X3D sample Lisa Su was holding into the camera over a year ago? Let‘s hope Intel can put the competition pressure back to AMD so AMD stops acting all Intelly circa 2013. :(

[@Fractal_32]

Honestly I would get a 3D Vcache version if that means I can run slower ECC ram since you could get the best of both worlds: good stability and good performance.

[@abavariannormiepleb9470]

3D Vcache would even help out a bit with power consumption since main system memory can be accessed less and clocked lower making the whole platform more attractive. Fuck the responsible product managers.

[@ertai222]

You don't need 7950x3d. It's a productivity chip. It already isn't that great for gaming so the cache wouldn't be that helpful. The only chip that makes sense for gaming in a practical sense is the 7800x3d. If you do work just get the 7950x as the 3d version isn't going to be any better. The productivity applications won't benefit from the cache. If AMD even makes one it won't be anytime soon.

[@abavariannormiepleb9470]

It is not wise to project your own computing demands on other people. Not everything revolves around gaming and there is a reason AMD released a few Milan-X SKUs but only a Ryzen fig leaf. And that reason isn’t that AMD is looking out for its lower tier consumer platform wanting to help customers not accidentally buying a 3D CPU that’s a bit more expensive than the non-3D counterpart.

[@Ultrajamz]

Curious how this is aged after a year of BIOS updates

[@devemia]

The content I have been waiting for. I always want to see how far can these platforms go with extreme memory size. Finger cross and see if Buildzoid will also test 128GB on AM5.

[@Yock1980]

AMD and Intel really don't want you to use consumer chips for workstation work any more.

[@Bayonet1809]

Have they ever? The real issue is that HEDT are now utterly unaffordable. I remember when the i7 920 was common.

[@Yock1980]

@@Bayonet1809 Having to shell out 2k+ $ just to get more PCIe lanes is moronic. We have multiple PCIe slots but can realistically only use 1 maybe 2 of them. Worst thing is that it's kind of blatant what they are doing when only giving us 24-28 lanes.

[@billlodhia5640]

​@@Yock1980 I like how Asus does the PCIe setup on their WS X570 ACE board, it really helps out in terms of expanded PCIe capabilities (at the cost of some extra latency I'm sure)

[@johnscaramis2515]

I think 128GB support needs time to mature. In the end we're talking about consumer boards and board manufacturers will test RAM and optimize UEFI settings for the memory configurations which are around the sweetspot for consumers, so 16GB or 32GB in total. And Intel has the 2nd gen CPUs with DDR5, so it can be assumed that they have improved the IMC in Raptor Lake compared to Alder Lake. If I remember correctly, early adopters had also issues with DDR5 compatibility. So let's wait and see what AGESA and UEFI updates bring in the future.

[@thepopeofkeke]

First build 13900K 128gb Corsair dominator platinum 520hz. Evangelion z690- no problems 4800hz out the box. Can’t get xmp to work. 🤷🏼‍♂️

[@KieranDevvs]

Well it's not just 128GB, it's 64GB if you're using 16GB DIMMs

[@ChatGTA345]

@@thepopeofkeke this cannot be true unfortunately, I suspect your settings are unstable. Even 13900K cannot run 128GB stable greater than 4200ish, all manufacturers tried and failed at it

[@joshxwho]

This is a great video! Thank you for talking about this, and for talking about the ddr5 inserting issues.

[@pb3d]

you just saved my sanity with this video... as it has been a few years since i last built a machine, i would never have expected the limitations we currently face with 4 DIMMs. 10minute Boot times? No freaking way... but yet, here we are. Got my 128GB to run at 3800MHz, will have to see if its stable though.

[@simonthibodeau7082]

I'm currently running 128gb DDR5 at 4600mt/s with my 7950x. They are two 2x32gb kits of corsair CMK64GX5M2B5200Z40 (5200 mts c40). Those kits were pretty cheap compared to most lately and probably still are today. That's the max I was able to run them on both an Asus proart creator wifi x670e board and an asus prime x670e pro wifi board. Both running at docp profile 1 and setting the target frequency to 4600 (no other tinkering, using the latest bios which you do need to update!). Above that it won't boot. Not officially supported but I think its the most bang for the buck 128gb configuration I could find. Hopefully this info can help some people. Maybe I could manually OC to squeeze a bit more but I've read of instability issues so I don't bother with it. I might upgrade in the future when true 4 stick kits become supported, available and affordable. Imo buying more expensive ram than my config is just not worth it as it's pretty clear something much better will come along eventually and you're gonna need to upgrade anyway, even if you splurge for the higher end ones now. I kinda also doubt the current kits will get that much better support through bios updates as many manual OCers have tried their best to push them to their limits in 128gb configurations with no success. I don't think a docp profile that actually can get them to their rated max speed is even possible. Thanks for this great video. Wish this video was available when I made my build, it would've saved me a ton of digging in forum, trial and error buying the wrong things, and tinkering around in the settings. I'm sure it'll help out a lot of people. Ps: my boot times are very fast now, once the first boot was completed. The memory training time on first boot is always very long, and annoying since you never know if it will eventually succeed or not. If you follow my config you should have no problem matching my results easily and get a very usable working 128gb setup at a somewhat decent speed. Cheers y'all! Pps: heard the expo version of my kits currently have a bunch of issues, my local shop has stopped carrying them. I recommend you get the regular xmp version like me.

[@thealien_ali3382]

I had 32gb ram and I double to 4 sticks so 64gb pc was stable for days speed was 5200mhzt then got a blue screen heard if u reduce the speed should be fine, so I reduce by 200mhzt running at 5000mhzt gonna see if it works, but two sticks even at 6000mhzt is fine.

[@DemoAkuroVR]

What voltage are you running the sticks at?

[@Kumodot]

I was running 2x32 blades of Vengeance CL32 6400Gbz at 6000Ghz with no issues. Today added 2 extra blades and my hell started. Updated the Bios before installing them. Got them recognized at bios, boot, and no POST or windows Anymore. I was only able to see the bios again removing PHYSICALLY the 2 new blades. So i see the BIOS, was able to down the speed to 4000Mhz, put the blades again, and finally it boots. (But it took me some hours in the process of trial and error. And Having to remove the blades each time to see the bios is a nightmare. Now i am running 128Gb at 4000Ghz. Gonna re-read your post and try to squeeze more of it.

[@jjdawg9918]

Thanks for addressing the 13900K since that would have been the next question. It can't remember a time when the memory technology was that far ahead of the memory-controller technology and this is Intel's 2nd round.

[@ChatGTA345]

ikr 😢

[@YesterGearPCii]

Recently I built a 7950 system (Asus x670e ROG Crosshair Extreme) for a deep pockets client. He ordered 128gb of Corsair Dominator Platinum RGB 5200. With all 4 sticks, it would never run more than 3600mt/s, and took 20+ minutes to train/post. With just two sticks, it would hit 4800mt/s (still not the 5200 advertised), and enabling manual DOCP would refuse to post even after an hour of training. We were both a bit confused and upset. He currently decided to stick to the 64gb.

[@ABaumstumpf]

"still not the 5200 advertised" Cause NONE of the memory those brands sold is official DDR5 5200/6000/whatever. They are all overclocked, way different timings, way higher voltage/power. Right now we are just seeing the first few JEDEC 5600 kits arriving, 5200 for a bit longer - but JEDEC 5200 means 38 CAS and 1.1V. But most memory that you can get is glorified overclocked DDR5 4000-4800.

[@YesterGearPCii]

@@ABaumstumpf I understand that JEDEC is all that's guaranteed. However, they advertise DOCP at 5200, and the set was on the QVL for the mainboard, so in theory it should work, and was advertised to do so.

[@AvgDan]

I have the XMP version (F5-6000J3040G32GX2-TZ5RK) and 7950x. Was hoping to upgrade to 128GB down the road. Hopefully future AM5 CPUs will have a better IMC to support DDR5 6000 with 4 DIMMs.

[@nemesis1588]

64GB DIMMs would probably be easier

[@joshuafalck_]

My experience with modern DDR4 and DDR5 has been a pick one of two. 1). Lots of RAM at lower speed and higher latency. 2.) Some RAM at high speed and low latency.

[@MrMaddog2004subscribe]

Yep, unless if with DDR4 you want to spend a good amount more money then you can somewhat get both, but usually its not worth it

[@Winnetou17]

@@MrMaddog2004subscribe Spend money to get better what ? Memory ? Motherboard ? Isn't this mostly a memory controller limitation ?

[@grrkaa8450]

@@Winnetou17 RAM binning is a thing, RAM that's running on the edge won't be stable even on the best matured CPU/Chipset

[@michaeleber4752]

Wonderful presentation. This is the first video of yours I've watched and it is a breath of fresh air. I've seen way too many channels where the speaker has no script, has not idea what they will say, and half of their presentation is them correcting themselves or not saying anything at all.

[@ahuesphoto]

The video is interesting, this “next room approach” is actually practical in most homes. I used to think that water cooling was a necessity for a Silent Gaming PC / Workstation until I tried positive air pressure (inside the case). With positive air pressure and enough high-quality fans in the proper orientation and a good enough case you can enjoy a silent PC with near water cooling temps (less than 60 Celsius under load). I use Arctic 120mm fans, they won’t go above 1000rpm often, and they are not expensive like Noctua fans. In my personal experience the Best orientation for air is top to bottom with PSU fan facing inside the case (as exhaust fan), and front to back with a WS case (with 3 front fans). Even blower style GPUs get cooled efficiently because of the fresh air being pushed / moved constantly inside the case. The key is to have more / faster intake fans, and less / slower exhaust fans, and not to have conflicting / opposing airflow; this way the air moves quickly and the fans don’t have to spin up to higher RPMs.

[@jonathanf4082]

This is information I wanted to know and couldn't find elsewhere. Great video.

[@machinimaaquinix3178]

Aw awesome! I was just looking for advice about this topic yesterday. I can't believe with the newness and pricing of AM5 motherboards, the IMC is such a problem. For now I'm going to go with a B650 (why 670 with the same iffy IMC?) and only 64GB. Sadly, going to Intel for 128GB seems to not really bring much benefit. Ya, I'm poking at you Intel also.

[@porkbork3500]

Wish I saw this video first before buying 2 pairs of Corsair Vengence 5200mhz kits for 128gb total. Luckily I didn't buy high end ones, which would have wasted the chip speeds. On my MSI PRO X670-P WIFI with 7950x I was able to get a stable 4600mhz - it passed two PassMark memory test runs. 4800mhz posts and boots, but fails memory test. 5000 and over does not post and need a CMOS reset (or take out two of the chips to boot and change bios settings)

[@norbertdrage]

Please tell me I'm not the only one chuckling at the irony of a board called the Steel Legend being made up of mainly plastic 😆

[@Yuzuki1337]

The all new ASPaper Plastic Legend :D

[@grrkaa8450]

it's Asrock, they have decades of consistent mediocre-to-poor quality and reliability on their record

[@elevated5096]

That MB that he mentioned was mostly plastic was the Aorus one, he just happen to put it on top of the Steel Legend Box.

[@pbody1761]

For AM4 boards I only had troubles with ASRock, never issues with other brands. I had a b350 fatality with a 1700, and a b450 fatality with a 3600. Both motherboards wouldn't go over 2800mhz ram with 3600mhz sticks. Then I grabbed a b450 Asus board and put the Ryzen 5 3600 in it, and the ram will OC to 3800mhz with same timings as 3600mhz.

[@rudypieplenbosch6752]

I also want to upgrade my AM4 3600 64GB (2dims) to 128GB 4dims. Are you saying I can expect problems with that ? 🤔

[@Sonickid1011]

I had similar issues getting just 64GB of DDR4 4000Mhz running even XMP on my x570-ryzen 9 5950x setup. I eventually got all 4x dimms running at 3733mhz with an fclk of 1866 but it was a pain in the ass with a lot of testing and restarts and instability.

[@Charlie-zj3hw]

I have to give you some praise on your camera quality and your lighting!! Watching on a QD-OLED is amazing! I wish more youtubers would step up the game! Great job!

[@LastWeekInTheWorld]

Has any changed regarding this matter? Has there been a bios update that makes it possible? Is there a new mem controller on the 9000 series that make 128 GB at 6000MHZ possible?

[@benjaminoechsli1941]

Thanks, Wendell! Hopefully things will continue to to improve with the X3D chips and the eventual Zen 5 series.

[@vortexsophia]

Thank you for this exact video. I was just about to put together a 7950x ASUS Hero X670 and 128g of trident Z Neo just like this for a new workstation. I'm glad i'm holding off. My 5950x is running 128g nicely and i'll just wait a good while

[@DerekDavis213]

Why would you need 128gb with a 16-core processor?

[@nathanlowery1141]

@@DerekDavis213 large RAM disk for converting movies without killing your ssd or waiting for spinning rust

[@vortexsophia]

@@DerekDavis213 AVID media Composer. it uses most of it. Use lots of single core application that preferer high clock speed instead of threadripper. My 4090 does more workhorse than the 5950x :)

[@DerekDavis213]

@@nathanlowery1141 An recent nvme ssd can read and write at 7000 megabytes/sec. An Intel Optane drive has very high performance, for smaller queue depths. How much faster could a RAM disk be?

[@DerekDavis213]

@@vortexsophia You are using AVID? And I thought that all serious editors use Mac and Final Cut? Just kidding! Mac is overpriced garbage.

[@prjndigo]

It should be able to address 1TB total. Expecting it to be any faster than junk in the first implementation when they should have been making some kind of high-speed HBM3 module and socket system is idiocy.

[@timgonzo]

Thank you so much for uploading this. This is exactly what I was concerned about for my new build.

[@LeitoAE]

I bought used B350 motherboard with 1700x, that had pretty old bios and 2666mhz Adata 4x4gb kit. I could not make it run at 2666. 2400 had stability problems and only 2133 worked fine. After bios update it could easily run 2666 and then when I upgraded to 3200Mhz kit it also run fine at 3200Mhz without any issues, so a lot of memory problems on first ryzens was solved by bios updates. I also think that memory manufacturers had to learn "AMD" again after being abandoned for a while. It was a lesson for both - motherboard and ram manufacturers to get back into AMD and make some compatibility tuning. I don't know how it was before, but now I even do not have to tune the Infinity Fabric. It always automatically sets itself to 1:1 ratio with memory.

[@kamikaze00007]

Some people have told me that they could get the 5600 Trident Z kits to run 128GB stable by first letting the board and CPU memory train with 64GB, and then later filling in the rest of the 128GB and manually setting the speed to 5600 with auto on voltage. This was apparently with a Gigabyte X670E Aorus Master board. The kits they were talking about were the ones without EXPO, but labeled as Hynix within the Aorus Master's own QVL list page.

[@thealien_ali3382]

I can't run 5200mhzt on 4 dims ddr5 on a x670e hero with a 7900x, 4800mhzt works fine on 4 dims

[@chromerims]

Top shelf reporting 👍 Thank you Wendell

[@ChatGTA345]

Could you please address the same issue with Intel? The situation doesn’t appear to be any better over there 😢

[@raymondallen7209]

I can't thank you enough for the heads up on the memory I would been waiting for that snap in sound.

[@urblotasunkynewulf615]

Any updates to this?

[@porina_pew]

Gone through the same pain with 4x 2R DDR4 sticks on dual channel platforms. I think high end consumer is long overdue getting an upgrade to memory channel support and should go where low end HEDT platform was.

[@rkan2]

I'm not sure there is actually much that can be done unless you go to something like dual sockets...

[@rayw8252]

@@rkan2 He means bringing back consumer Threadripper / X299 platforms. Quad channel memory.

[@TimCristy]

I'm shocked its working, but I'm running a 2x16GB kit of G.Skill DDR5-6000 CL30 in the A channel and a 2x16GB kit of G.Skill DDR5-6000 CL32 in the B channel with a 7900x. With EXPO set its actually running all 4 DIMMS at 6000 CL30. Its passed the stress tests I've tried and I've been using it for almost a week now without any problems.

[@СусаннаСергеевна]

Check your actual bandwidth, though. I've got four sticks of 2x32GB-5800 running stable at 6000, but the actual bandwidth isn't much better than running them at 4000, which is probably because the fabric downclocks to relieve the memory controller. Worse, because of whatever is happening in the background, my cache performance also suffers. Depending on your workload you may not actually benefit from running the memory at those speeds.

[@Bayonet1809]

4x16GB presents similar strain to the IMC as 2x32GB, so your achievement is no better than Wendel's here.

[@kane587mad]

Using more than 4 ranks was a problem in any RAM generation since SDR. That's why you should avoid dual rank RAM if you want to add more later.

[@PrivateUsername]

Be sure to reference the DDR5 spec when talking about this. Section 10 talks about the speed bins and what you should be seeing, all the way up to DDR5-8400.

[@GeekProdigyGuy]

I sincerely hope that, with later CPUs or BIOS updates, current boards will support 128gb...

[@abavariannormiepleb9470]

Yes, in 2025 when the first 64 GB DDR5 UDIMMs come to market ;)

[@Bayonet1809]

They already do support 128GB, just at slower speeds. Future CPUs will probably have improved IMCs, allowing for improved memory speeds.

[@GeekProdigyGuy]

@@Bayonet1809 yes, technically, although I think that when you're talking about 30% reduction in bandwidth by plugging in more sticks the "support" is pretty much just nominal... but yeah, as I just upgraded and plan my next upgrade for ~2y from now, being able to go from 2x32GB to 4x32GB along with CPU upgrade would be ideal.

[@profosist]

Ill be trying the 64GB (2x32GB) of Trident Z5 6000mhz CL30 on a 7700 system shortly. Really happy they launched with non RGB variants.

[@ChatGTA345]

oh they did? I couldn’t find a retail kit recently

[@profosist]

@@ChatGTA345 yeah just got it during Black Friday for a build so glad I don't have to get RGB I can't turn off

[@ChatGTA345]

@@profosist Haha nice! I'm building one now also, but wanted to get non-RGB perhaps cheaper because I'll put it under water

[@emperorSbraz]

hmm I hard disagree on testing with memtest86 - it's OKAY to spot complete faults but as for stability naah gotta stress in windows. corrupting the install can happen though that's true.

[@abavariannormiepleb9470]

And/or use one of AMD’s feature advantages of not disabling ECC by default and use a motherboard and memory with ECC support. Have many AM4 systems with 128 GB of ECC memory and no issues with DDR4-3200.

[@r.j.sharkey]

and never do either on an arc fault breaker (without a UPS)

[@Werdna12345]

There’s a typo on your hoodie. It should say “…your computer, Linus.”

[@mattp1680]

I built my new rig in October with a 7950x and 4090, I have 4 x 16gb DDR5 6000mhz RAM, it's the Kingston Beast EXpo Ram. I have been having very slow booting and occasionally (once a week or so) it won't boot at all and requires a CMOS clear to get into Windows. The machine is an absolute beast when in Windows and running well and it holds 6000mhz without stability problems but these little annoyances with booting etc do get old very quickly, for example my old AM4 system booted into Windows in less than 5 seconds, I'm closer to 45 secs to 1 min with the new machine. I wasn't aware that 4 DIMMS could cause an issue with X670, wish I'd gone with 2 x 32gb kit now. I will try to remove a couple DIMMS and do some testing, see if the boot times and stability improves, thanks a lot for bringing this to light, not a lot of people are covering these topics

[@drakcoreoriginal]

Was running a 7800X3D, 64GB (2x32GB) RAM @ 6000Mhz. Upgraded to 7950X3D 128GB(4x32GB) @ 3600Mhz. The RAM does take a big hit. Tried even at 4800, 4600, 4400 and 4200MHz. No luck. Just gave up and left it at 3600MHz.

[@evalangley3985]

8:00 "It was clocking faster on Ryzen 1000 and 2000 series..." Nope, you are mistaking on that. I owned a 1700x and never was able to clock my memory above 2900MHz on the first AGESA BIOS update. It was fixed after around a years. Same thing will happens as AGESA update are going to drop.

[@СусаннаСергеевна]

I guess I got _really_ lucky, then. I'm running two 2x32GB-5800 kits on my 7950X and they'll even overclock to 6200 (well, momentarily, I invariably crash before my overclocking live USB gets to KDE). I have been running it at 6000 with conservative timings since I put the system together, though, and it's been remarkably stable (no errors in over 24 hours of memtest86). iGPU also works fine (though I still haven't been able to pass it through to a VM...) Booting is ridiculously slow of course (about fifteen minutes, thankfully I hardly ever turn my computers off), which is why I've been restraining myself from trying to improve the settings. Measured bandwidth varies wildly from boot to boot, mostly some flavour of poor, but I do sometimes get good performance. If I wanted speed more than capacity I'd be better off running a single kit, having both kits in at once definitely kicks the memory controller into some fallback mode where performance plummets so in terms of actual bandwidth I rarely get over 90GB/s, and worse, it actually does hurt my L3 performance quite severely (I've seen it go as low as 800GB/s, but mostly it hovers around 1500-1700), but it is still technically four sticks running at 6000, and going down to 3600 or so to not hurt the L3 will benchmark worse. This isn't EXPO RAM, though, and I am running it at a very high voltage. Running a single kit at a time lets me push much higher clocks and bandwidths, so it may simply be a matter of winning the silicon lottery five times in a row (memory controller and all four memory modules). I'm eagerly awaiting new BIOSes that may reduce boot times a bit, I suspect that running all four DIMMs does bad things to the infinity fabric, which decoupling fabric base clock from CPU base clock may help resolve, but when it takes twenty minutes to check each change I make I simply don't have the time. Even if all this capacity does hurt cache and processor performance (and it certainly does, I just cba to find out how badly yet), it's still less bad than swapping to disk would be. I've been pleasantly surprised with AMD this generation, and my expectations were already pretty high. On my 12900K these same memory kits, even alone, couldn't boot on XMP. The best I could get out of them was 5600. At least the timings were good. Normally I'd expect Intel to overclock memory better even though AMD is more dependent on high memory clocks, but here my experience has been that Intel can't overclock at all while AMD performs miracles. That said, 90GB/s on DDR5 is pretty unimpressive when I was hitting 100+GB/s on DDR4 several years ago. A last generation Threadripper would get me much more capacity at comparable bandwidth, and it could even be ECC without an awful lot of bother. The extra cores mostly compensate for the loss of per core performance. I really think two DIMMs per channel ought to die. Either give us four channels outright, or make motherboards with only two slots. As it is those few of us who do benefit from running four DIMMs in a computer should just pay the EPYC tax and get a proper workstation instead. Much higher capacity. ECC. IPMI. A sensible amount of PCIe lanes instead of the utterly inadequate pittance they deign to throw us filthy plebeians.

[@Bayonet1809]

No, you did not get lucky. Wendel is talking about 4x32GB. 2x32GB was more than capable of running at 6000MHz.

[@СусаннаСергеевна]

@@Bayonet1809 I wrote that unclearly, I'm doing the same thing Wendell is. Two kits of 2x32GB = 4x32GB.

[@Bayonet1809]

@@СусаннаСергеевна Wait, so you are running 4x32B DIMMs at 6000MHz, fully stable? Could you please say what exact RAM kit part number you used and on what motherboard?

[@frzen]

Can you post details about this on the level1 forum there are several people who are stuck at 4600 and if you have 6000 stable then that's amazing

[@mattehartog]

Seconding this, if you could post on the level1 forum thread in the video description, that would be really helpful. Thanks so much!

[@TheLevitatingChin]

Just got 128GB in my home server based around a 7950x. Works great 👍

[@strayedwinds]

Is it still doing any good and stable sir?

[@ChowHound1337]

I think this should be revisited soon with all the recent updates

[@bill_and_amanda]

BuildZoid has been arguing for a while that 2 DIMMs should be the be standard on DDR5 motherboards, not 4 DIMMs, because of the inherent speed advantages with DDR5 and resultant difficulties with running two DIMMs per channel. Seems like he might be correct.

[@penguinbelly]

What if you need more memory a year from now? It’s so much easier to add 2 more sticks than to build the whole thing from ground up.

[@bill_and_amanda]

@@penguinbelly I think the point is that the way DDR5 is designed, the architecture of it, makes having multiple DIMMs/dual rank either have no advantage or even actively make things worse, so you'd be better off selling your existing two DIMMs and buying a higher capacity set of two.

[@bill_and_amanda]

kzbin.info/www/bejne/h2m7famQidasjpo

[@GeorgeTsiros]

the dimm slot is a component sourced from another company. nothing you see soldered on the motherboard is made by the motherboard manufacturer. You will find slots that do the automatic click thing, you will find some that don't. It is not an agreed-upon standard

[@penguinbelly]

Then what does JEDEC do

[@darkforcesjedi]

I don't need ridiculous amounts of bandwidth. I just want 256 GB of RAM so I can use most of it as a storage cache, but still have enough RAM to use Adobe apps. I have 64 GB now and occasionally will use it all just with Lightroom and Photoshop running.

[@jasonhurdlow6607]

Honestly I feel like AMD shouldn't advertise 128gb RAM support until it really works properly. That or MB makers should just put two slots on their boards and call it a day.

[@penguinbelly]

128 GB support has been there since AM3 days. I do not know what you mean by "working properly," but it seems to work fine, albeit at reduced speed. That is not on AMD but physics. Every memory controller in existence has had the same limitation.

[@Murph9000]

Pretty much all of the ASUS memory QVLs that I've looked at for both Intel & AMD DDR5 boards currently only have 2 DIMM configs listed.

[@IrocZIV]

Thanks for this coverage. The main reason I haven't upgraded to a new platform is I want reasonable speeds at 128GB. Had been leaning towards Intel DDR4 since there are several motherboards that have QVL 128GB at 3600.

[@ChatGTA345]

I really wish this situation was better for either platform. Rn “upgrading” from AM4 128GB to Z790 64GB :/

[@penguinbelly]

May I ask respectfully what it is you do that benefit from RAM more than 64GB? Out of curiosity.

[@ChatGTA345]

@@penguinbelly For me at least it's a lot of software development work, which needs surprisingly quite a bit of RAM, incl all the browser tabs and microservices spread among multiple projects

[@silverbackag9790]

@@penguinbelly workstations for rendering and power users with home/small businesses servers (video, XFS, etc). I can’t see why you’d need it for gaming or most other applications.

[@shammyh]

Very interesting analysis!! Don't think I've missed having a proper HEDT platform as much as I do right now... Sure, I could spring for Threadripper Pro... But I don't really need 8x channels of RAM and >64 pcie lanes on my workstation. What I do need though, is >16 lanes of CPU-based pcie, and ~4x channels of memory... And there's really just slim pickings out there right now to meet that requirement.

[@KevinPJensen]

>7 days ago 😵‍💫

[@YukiGibson]

@@KevinPJensen yeah wtf??

[@shammyh]

@Dmitry Akimov Nah. I just have a time machine.

[@Dave5281968]

I recently built a new computer with a Ryzen 7 5700X on an ASUS B450M motherboard with two identical G. Skill DDR4-3200 32GB kits and ran into the same thing. The spec says 2933MHz maximum for four sticks of DDR4. I was able to get the system stable at 3000MHz, but some of the memory timings had to be set very loose, and it took alot of tuning to even get the 3000MHz going stable. At 3200MHz the system would absolutely have tons of memory errors, regardless of timings, and sometimes would not even POST. I'm guessing DDR5 is even more finicky due to the significantly higher clock speeds. Thanks for the video. You've confirmed what I though was the case here with my computer: The memory controller is simply not up to the task of being overclocked with four sticks of RAM, even single rank.

[@cygenta_modernCRTgamer]

Thank you for this testing! This is a lot of work

[@callowaysutton]

I’d hate to see how tedious higher capacities would be since 256GB is technically possible with DDR5. Haven’t even seen any 64GB DDR5 UDIMMs outside of the server space yet…

[@erickcoutsii9499]

I would suggest enabling spread spectrum if you end up with dual-rank memory side-by-side to help stability.

[@chrisbradley9607]

How does this help though? The same clock to both modules gets modulated.

[@erickcoutsii9499]

@@chrisbradley9607 By somewhat blurring the signal of the modules, the read and write cycles can be written to each chip without having to worry about directly affecting the chip on the next board next to it by writing at a similar frequency. Think of it like being slightly off-key from the wine glass so it doesn't break, only electronic.

[@chrisbradley9607]

@@erickcoutsii9499 I understand how SSM works. However, what I don't understand is how it makes any difference since the same PLL generating the modulated signal is fed to both modules. They are both fed the same modulated signals so there is no difference. Doing SSM on a per module basis would create intermodulation beat frequencies. Also, SSM is typically not for signal integrity but reducing quasi-peak emissions.

[@ripiosuelto]

You are one of the first to address this important issue 👍

[@ShinigamiDa]

Can you please do memory intensive benchmarks for 128gb running at 3600mhz (AMD Recommend level) and compare with 5200/6000?

[@PoizenJam]

I would LOVE to see this video for the Z690 or Z790 platform with the new 13th gen processors. I cannot, for the life of me, find a comprehensive overview of what one can expect on those platforms with 4DIMM configurations.

[@asm_nop]

High speed links like memory and PCIe really seem to be making life hell for platform engineers, lately. DIP-socket SRAM and ISA, SIMMs and PCI, DIMMs and PCIe. Every time they start hitting a wall, they change up the form factor. I wonder what comes next.

[@c1m1w]

Flush mount sockets rather than slots help. This is Dell’s DDR5 laptop standard, and nvidia’s gpu socket. After that it’s cables.

[@dgo4490]

The IMC is underbuilt for that much work, the good thing is it is in the IO die,so a simple revision of that would suffice to improve things, no need to fiddle with the core chiplet whatsoever. Remember, zen was and pretty much still is a server design adapted for other use.

[@Petch85]

Ahh this sucks. I was hoping to upgrade to a 7x00X3D system with AVX512 and 128GB 6000 ram. But that looks unlikely now. What do we know about the ecc capabilities of ddr5? Is it any good?

[@choppergirl]

Dunno, I've been doing it fine for the last 6 months. Just disable XMP / EXPO. Run it at the stock safe 3600 or 3800. You have to match the two kits you buy exactly.

[@blackasthesky]

If I had to choose a board manufacturer based on what features they offer I would go with MSI. Their Memory Try It is awesome and they put debug LEDs even on budget boards. For me their boards are just king of trouble shooting.

[@TheEclecticDyslexic]

Thanks Wendell! I wasn't sure if I should go 2x32 or 4x16 when I do my next build. That settles that!

[@milosavpavlovic7548]

I ordered 4x16 if I understood correctly 2x32 is better?

[@xDLiLi1337]

@@milosavpavlovic7548 2x32 is better but it would need to be dual rank

[@paulkendall6069]

I think the problem lies in these areas Power Available, Heat produced that builds up in the Chiplet package and bandwidth and timings that the memory/board(Build Quality&Chipset) & CPU can successfully communicate in. No point AMD running 4 DIMs to the max if your getting errors then having to repeat cycle or worst crashed system.

[@AthamAldecua]

I ran 4X16 GB of DDR5 at 6000 mts for 13 months, (7800X3D, X670E steel legend, automatic EXPO) no problem. Until suddenly, one day, I started getting random BSODs or a frozen, unresponsive system. I don't know what fucked it up. Maybe a windows update. I am currently running them at 5200 with good timings, and that seemed to stop the random crashes. I am getting a 2X48 DDR5 kit next. Four dimms in AM5 is a bad idea and I did not know it at the time.

[@iliaskapatos]

WOW 4x32 GB Trident Z5 NEO are now running on the ASUS x670e Hero at 5000MHz my settings are: Tcl: 36, Trcd: 36, Trp: 36, Tras: 77 the speed for the 4DIMMs at 128GB improved now to Read: 68'330 Write: 72'765 Copy: 67'461 Latency 76.0ns.. But whatever I try at 5200MHz will fail until now, but 5000MHz is better than 4000MHz. The Curve Optimizer for my 7950x CPu is: all cores/ negative/ 16. If I can get the 128Gb to run faster than read 70'000, then I would post again.

[@spidersj12]

Disappointing given the presume potential of a 7950x rig to replace those people with a Threadripper 2950x at a "decent price point". Yes the DDR5 RAM is crazy expensive as are the highest end motherboards. In time prices might fall, UEFI might mature and imorove on these current and future AM5 motherboards?

[@NVMDSTEvil]

Would love to see videos like this for server level hardware to see how performance changes based on timings, chip density, number of ranks available per channel, and etc.

[@martinmaurer7830]

Where are the problems with 4 DDR5 coming from? Is it something which can be fixed in future by a BIOS update by AMD and/or by motherboard manufacturers? When the motherboard manufacturer offers 4 DIMM slots for DDR5, and it is not really possible (at least not now?), is it not a reason to give the motherboard back or get a price reduction, when I already bought it, but want to keep it? Is there a size limitation per DIMM? So could a DIMM bigger than 32 GB be a solution? So 2x64GB could be possible and a solution for the future? What is the maximum DIMM DDR5 size, which current system support? Same problems on "the other side"? How is it going on Intel side with 4x DDR5?

[@martinmaurer7830]

kzbin.info/www/bejne/pp6mg5ppn9uZf80

[@jjdawg9918]

At At last.Thanks so much for doing what no one else will! Anyone running VMs, AI etc will appreciate this (and Firefox can eat 10G alone..don't know if it's memory leaks or my open 20+ tabs, but it's a hog ;-)

[@lukaswerner4390]

Shouldn't be mem leaks because of rust borrow checking

[@erisdiscordia5547]

There must be something wrong with your profile or something, I'm easily running Firefox with 1500+ tabs on a host with 16 GB RAM

[@AvgDan]

@@erisdiscordia5547 click on each tab so it loads the content for the page the tab represents. I had Firefox open and using 2.5GB of RAM but after clicking the other tabs that were from prior sessions it jumped up to 4.2GB (32 tabs total). I'd imagine 1,500 tabs would use quite a bit more than 16 GB unless Firefox starts unloading content for tabs that aren't one of the past nTabs viewed. Now my 4.2GB for 32 tabs vs his 10GB for "20+" tabs is a bit mismatched, so he might have an issue, but it's also possible there's much more content loaded on his 20+ tabs than my 32 tabs.

[@daa3417]

@@erisdiscordia5547 nonsense unless those tabs have yet to be loaded, and if so what good are they? All modern browsers are memory gluttons, and I suspect that trend will continue so long as developers have more and more memory overhead to work with.

[@ChatGTA345]

Ikr, everyone is talking about creators but it’s just as painful for power users who like to research stuff without closing the tabs 64GB out of 128 on my last system was just hogged by Chrome I swear (with multiple Chrome profiles etc.) Gotta adjust our habits now I reckon 😅

[@hishnash]

The bandwidth speeds you mention do sound so low. Are these single core bandwidth or is that the real limit of the full multi core bandwidth of the chips. I am sitting here with an M1 Max MBP im thinking my single core bandwidth is 2x that let along the multi core bandwidth.

[@piro133a]

Not sure If this relates: I have a lenovo legion 5, 4800h laptop with 64gb of ram (i know not the same as am5 at all but stick with me). For the longest time I thought my sticks were bad because I would get memory corruption. It was actually something to do with the IGPU and switching between Linux and windows. Something was not getting reset! If I went from Linux to windows I would get BSoD.....then memtest would show issues too. My theory is that between boots the igpu was still holding onto some of the system memory....it wasn't being properly released. Enabling/disabling the igpu....different Linux distros....different ways of rebooting (doing an actual power off vs rebooting) all yielded different results in memory stability.

[@piro133a]

And before you ask.....this memory could go through an entire 24hrs of memtest and not have problems. It was 100% not the sticks themselves.

[@aegiltech]

Remembering first generation Threadripper, and it was almost a year before we had good bedded down memory. Starting from a better place this time, but still a long way to go.

[@fragrancefree]

Got my new PC up and running. Intel i9-13900k, Asus Z790 ROG Hero MB, 8TB RAID NVMe RAID array, 4090, and 128 GB G.Skill 6000Mhz DDR5 RAM. PC kept crashing with all 4 DIMMS. 2 worked fine. Ultimately disappointed I'm not going to be able to run all 128 GB of RAM but it's good to at least have a professional review on why I couldn't get this config to work. Thanks!

[@blakemccorkle18]

Did you try running it at a slower speed?

[@fragrancefree]

@@blakemccorkle18 Yeah, you can run all 4 sticks if you drop it down in to the 3000 Mhz range but that kinda defeats the purpose of the high end DIMMs.

[@darrengreen7906]

5800x, ASUS Tuf gaming with 4 * 8GB 3600 cl16 t1. Going to skip 7*** and maybe the next gen after. 5800x is far more power than I need currently.

[@JoannaHammond]

Even with the latest OMG, supports more memory AGESA I still can't get my G-Skill F56400 (4x32GB for 128GB) to go above 4200Mhz. With May version of AGESA I could hit 4200 without DOCP, now with the new version I have to DOCP to even hit 4200!

[@rando_commie]

same, kinda bummed out that i cant run half of the ram i paid for properly.

[@chassecourt8824]

For reference I just used this to get 2 Corsair 64Gb ( 2 x 32 ) up and running at 6000-30-36-36-76, I am yet to stability test and I was booting into linux.

[@---..]

I want stability, so I got ECC DDR5 so I could have error detection to know with confidence if I push the memory speeds too far without long term stability testing. Despite both AMD and ASUS (for the motherboard) claiming ECC support, it will not run in ECC mode. I'd love to see more content covering how ECC is useful for cases like this, and the sad state of advertised but not working AM5 ECC.

[@sadiquldey9095]

I've commented on many 128gb ddr5 video comments... I had a 13900k on a Asus Z690 MB, it couldn't run 32x4 ddr5 5600mhz stable past 4000mhz. At 5600mhz xmp, it just black screens, doesn't even boot into windows. Now if you're paying extra for 5600mhz or 6000MHz you expect it to run at that speed, not at ddr4 speeds. For now stick to 2 sticks, max 2x32gb 64gb kit.

[@muraddawod8331]

i like the tips about putting ram. it's really very helpful 💜

[@zombiedmon]

Thanks for the insight. Fresh build on an unfamiliar asrock board had me going crazy. All makes sense now. 👍🏻👍🏻👍🏻

[@ford1546]

Hello, I have a question that I hope you can give me a short answer to. have tried to find an answer without success. I have always used the same 4 pcs. 4GB memory chips 16GB. (CORSAIR VENGEANCE BLUE 1600MHz 4GB 9-9-9-24 1.50V) With an Asus sabertooth 990fx and AMD FX8350 It worked fine for many years until I installed win11. Then I started getting a blue screen. It took approx. 1 week between when it happened. After a lot of troubleshooting and testing with other memory chips, I found that only the first 2 memory chip slots worked. I came to the conclusion that it was the memory controller in the processor CPU. which was destroyed. Since this is not a new CPU, I managed to buy it used and cheap and had my theory confirmed. In the meantime before I bought a new CPU. then I built another computer from parts I had. A computer that was not quite complete. same year and actually the same system AM3+ but a different motherboard from the same year (Gigabyte GA-870A-UD3 v1.2) a typical gaming motherboard from that era. The strange thing was that the 4 of these memory chips I had did not work and my computer would not work. Then I took out one memory stick and replaced it with another memory stick (Corsair Dominator 1333MHz 4 GB 1.65V 9-9-9-24 XMP) and set memory chips in bios to 1600MHz and timing manually 9-9-9-24. it has so far worked perfectly without any errors. My question is as follows. 1. Why did I have to replace one memory stick with another to make my computer work? Do you have any theory on this? After testing, I know that all 4 pcs. stick works without problems. 2. I tried some Overclocking programs in win 11 which were unstable and destroyed another set of 4 pcs. memory stick, that's what I think was the cause. I hadn't even set anything in the programs since they crashed. Can such a program destroy a memory stick? Do you have experience or a theory?

[@whodat8048]

Thank you for saving me cash as I was definitely going to buy 128gb. You got yourself a new sub.

[@johnpaulbacon8320]

Wonderful video. The following are 2 - 4x 32gb ddr5 memory kits that are on Amazon : SABRENT Rocket DDR5 128GB U-DIMM 4800MHz Memory Kit (4x32GB) for Desktops and PCs (SB-DR5U-32GX4) this kit is $799.96 and A-Tech 128GB (4x32GB) DDR5 4800 MHz UDIMM PC5-38400 CL40 DIMM 288-Pin 2Rx8 1.1V Desktop RAM Memory Modules - this kit is $679.99. Maybe having 4 matched dimms might do a little better. I have 128gb on my current system ( AM4 ) build. At the time I put this together all of the parts were the best for there respective class - since then newer updated parts have replaced my parts as the best. The RX 6900xt was the best gpu class for gpu's from AMD now there is the RX XX50 replacements. Maybe the lack of a central memory controller might be a part of the issues at the moment.

[@shaneeslick]

G'day Wendell, WOW! 128GB RAM on Desktop, that is the size of my OS SSD😂

[@NetrunnerAT]

What is the Problem with Speed reduction If you use 4 Sticks? AM4 do exactly the Same. I use a AM4 System with 128gb RAM with 3400ghz RAM clock. This is OK. Also for heavy RAM usage. If you need more Speed threadripper is the way to Go. More Channels is every time a better choice before overclock RAM to gain high RAM GB/sec

[@penguinbelly]

I don’t think these people care about real speed. They care about higher numbers.

[@NetrunnerAT]

@@penguinbelly yea ... Classic spec war 🤣 for 2-4% more FPS.

[@samdeur]

thans for making this vid. very informative. When i decide to build my system I'll be stikking with 64gb as for me the 7900 only igpu is enough same motherboard

[@mrbdzz]

It’s probably due to physical signaling that DDR5 doesn’t clock as high when you have two DIMMs per channel. On the server side, for similar reasons, you have to use registered (buffered) DIMMs when you put multiple DIMMs per the channel to reduce the physical load on the memory controller.

[@mjsvitek]

Flashback to the X370 days when dual rank vs single rank memory sticks was a hot topic.