Choosing Between LGA1700 or AM5 (or LGA1851) with 192GBs of ram

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So, I’m currently in the process of building a new computer. I am finally upgrading my Threadripper 1920X / GTX 1080 ti desktop. I have a second mini-itx build 1700X / GTX 1070 I’ve used intermittently and both are starting to show their age. I built those back when I was in high school and just starting college. About 3 years ago I got a new laptop Razer Pro 17 with RTX 3070 (upgraded to 64GBs of ram) and honestly, it’s so much better I pretty much stopped using anything else.

So, currently for the build, I have dual 3090ti’s that I got on an insanely good deal certified refurbished <$1600 combined. I went with dual 3090ti’s because I really need vram and I am working on many projects for my part time grad studies and personal projects focused on AI/ML with big data sets and parameters. I had been using my work laptop (though I’m not really supposed to) for my projects up to now as it rocks a RTX A5000 with 16GBs of vram), but even that I am consuming the vram with even basic image recognition projects.

I do game but, honestly the games I play are still running at 120+ FPS on my 1440p ultrawide that I’ve had for 6+ years and have no desire to replace. So as long as I can game at 120fps at 3440x1440p I don’t care.

So, I’m currently been debating between AM5 and LGA1700. My biggest concern is, I really would like to eventually upgrade to 128GBs ram and above (192GBs) and of all the videos I’ve watched of Wendel and others reviewing AM5, it just doesn’t seem stable. I have mainly been looking at the Asus ProArt mobo’s as I’m currently outfitting my home lab with 10gigabit and I also like the thunderbolt ports as I do use many thunderbolt devices (my current setup is entirely thunderbolt run). It seems to me the LGA1700 is the most stable with 128GB but I’m not entirely sure on 192GBs. Given the LGA1851 might be coming out in October, would it be worth waiting? I might rig out my system on the threadripper and keep it chugging a little longer. The main thing keeping me leaning towards towards AM5 is that my AM4 ITX system has kept going so long where as my TR system is basically worthless with no upgrade path. My ITX system I could throw a new 5800 or something in and give to my wife or friend as a decent upgraded PC. This makes me think AM5 will be well supported going forward but I’ve heard about AMD dropping Aegis in a couple years and it sounds like they may just drop any new updates for AM5 in the future.

Thoughts? Should I put something together with what I got and wait a minute? Or go ahead and nab a 7950X3D and be satisfied.

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I had slightly similar considerations, minus this amount of RAM (I got 96 GB).
I decided to go with 7950x3d, since I like to game and I appreciate limited heat output, which is a problem with Intel. Please also note that you will need to use Windows for proper 3d ccd assignment for games, so might make sense to take the normal 7950x for other OS.

The Asus ProArt has USB4, not full TB - this means a thing or two might not work (USB4 specification is quite flexible in terms of not having some functions that TB has), please check your setup requirement against the given implementation.

If you plan to use more than 1 gpu, you should look at the number of GPU lanes - AM5 boards can have double 16x slots, but if you install 2 GPU, it will be actually 2x8. I believe that the best 1700 boards have more lanes and should be able to host 2 gpu at full speed. to be confirmed.

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From what I’ve found, AMD and Intel have made it so their non-professional lines of products have no more than 24 PCIe lanes with multi-GPU setups using 2x8 lane + x4 lane for M.2 drive + x4 to Chipset. Sadly both Intel and AMD have priced their high end desktop platforms so expensive I don’t see myself as buying either.

Thank you for the comment on USB4 != Thunderbolt, I had thought it was pretty much the exact same.

I think I’m leaning towards muddling through with my old Threadripper system until the new CPU’s come out as I’d really like to see if AMD’s next CPUs in the next couple months for more stable at high memory capacities as well as possibly improvements with Intels new platform.

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AM5 has 28 lanes available, though 4 always go to the chipset.

x8 on a 3090 Ti is barely noticeable, you’d have to build a $50k machine to notice anything as a user. We are talking < 2% difference on a consumer system.

If going AM5, the ASUS X670E Pro Art is a solid pick with regard to lane configurations. Not a perfect one, but solid.

You could also just slot in a 5700X for $165 on your 1700X. This will lower power draw and double your perf.

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The 7950X3D is a gaming processor. You can still work with it but if you’re looking for something that is chiefly used for content creation and game development I would suggest something else. There was someone here recently that was thinking of running 3090s in SLI or NVlink, as they call it now. Perhaps you’re the same fellow. I realize that you want to pool your VRAM for handling uber large volumes of data, but it has been my observation that this approach is all too often more trouble than it’s worth. One properly running 3090 should be sufficient for what you’re doing. Or, you could always sell them and get a 4090.

As I mentioned on the other post, you need to look at your total bandwidth. The 7950X3D has what - 24 lanes? You might discover quickly that you should have paid for more. My old, klunky ASUS X99 platform runs 40 and uses 128GB of RAM. Since I’m not a content creator (well, nothing big) I’m still running an NVIDIA 1070. BUT… Even when I run into demanding projects in data recovery, or video rendering, those extra lanes come in very handy. I recall ten years ago, when people laughed at me for getting so much system RAM. Nobody’s laughing anymore.

I did provide a word of caution concerning Thread Ripper on the other post so I won’t belabour the point but you were wise (IMO) to put a pause on that. So if you’re in no rush and you’re still looking for a system board to fit your GFX cards into, I highly recommend looking at something that will give you at least 40 lanes or more in the way of a CPU. 128 GB of RAM is not really considered a whole lot in the circles you will be working in. You should try to double this. A solid system board with 256GB of RAM will offer more stability than two 390s in SLI and only 64GB of system RAM. At least it should in most cases. So again, if you’re in no rush and you’re not chomping on the bit yet take your time. Perhaps going with an Intel CPU won’t be such a bad idea after all.

Of course, there’s always a chance that Snapdragon will get its stuff together in 3 years and turn everything on its head. But this is only speculation. Anyway, that’s my 2 bits worth.

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Here’s something to consider:
i9 10900X

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Interesting conclusion. Quad DIMM support on both AM5 and LGA1700 is DDR5-3600. Overclocks of 192 to 4800 are usually stable without much difficulty and the lowest I’ve heard of anybody getting stuck at is 4400. 5200–6000 requires more attention to thermals (as usual), often needs termination changes on AM5, and is more dependent on performance lottery.

In my experience the hardest part of 192 is finding 4x48 actually in stock.

Depends on your timeframe and enthusiasm for early adoption of Zen 5 or Arrow Lake. I’ve noticed a tendency to assume either is likely to run faster quad DDR5. However, it’s plausible limiting factors are the electromagnetic aspects of signal integrity with two DIMMs sharing a controller and lack of good airflow support in current desktop motherboard layouts.

Unless desktop processors go to quad controllers and DIMM layout rotates, I wouldn’t necessarily expect supported quad DIMM speeds to increase. ECC requirements are unclear from what you’ve posted but you might have better luck waiting on increased 2x64 UDIMM availability.

Yeah, really no direct competitors. So maybe the ProArts are worth the brand tax plus issues and risks surrounding Armoury Crate. Personally I’d consider also putting a 10 GbE NIC on a board with USB 4.

AMD’s committed to AM5 support into 2026. A common interpretation is Zen 6 or whatever will launch in 2026 with a different socket, in which case AM5 would have an Intel-like lifespan about half of AM4’s.

To add on to @wertigon’s correction of Zen 4 lane count, Intel’s chipset link is DMI x4 (not particularly relevant here) or x8. DMI’s essentially PCIe, so basically you’re most likely looking at a 4.0 x8 chipset link on LGA1700. Versus a 5.0 or 4.0 x4 link or two such links in series with AM5.

There are implications for lane sharing so, in general, review motherboards’ block diagrams to understand what connectivity and bandwidth is offered where.

Another path to four DDR controllers for 192 GB is configs like two 7900Xes or 7950Xes with 2x48 (and one 3090) each. Depending on workflow, performance priorities, and budget such approaches can be more attractive than scaling up a single build.

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There’s an entire topic discussing that in case you want to give it a go:

Seems like some folks managed to get 4x48GB working without issues at 5200~5600MHz out of the box. 48GB dimms seem to be easier to get working than 32GB ones.

I actually haven’t seen many positive LGA1700 results with 128GB, most can’t even go past 4400MHz, and some get stuck at 3600MHz (at this point you’d be better with DDR4).

I googled around and found some reports of folks with 14900k’s running 192GB at 5200MHz, so it should be doable nowadays.

Btw, if you’re working with ML, wouldn’t a Ryzen be more interesting than Intel due to AVX-512? Numpy gets a nice oomph out of it.

Nah, it’s pretty easy to get 2x3090s going without problems, and I say that as a owner of a couple of those.
No 4090 is going to beat 2x3090s, both from the extra vram and compute. Can both run bigger models (not doable at all with a single GPU due to the lack of vram), or double the batch sizes for double the training speed for models that fit within a single GPU.

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I’ve been of this mindset. Currently, I’m thinking of trying to lab something LGA 4189 or 4677 used. I’ve been eyeing a couple deals. Once again, luckily I’m in no rush so I can find good deals and work through it. I think I’ve found some decent prices for LGA 4189 but those more high end server stuff is a bit hard to find info on especially after they’re past their prime time.

I completely agree on the more PCIe lanes. My wife is currently totally screwed with her PC because while the CPU and graphics card are perfectly fine, the damn mobo only has a single x1 PCIe gen 2 port for expansion which has led to a ton of issues with PCIe capture cards, WiFi cards, literally anything because it so damn slow. Hell the board doesn’t even have M.2 and it’s an AM4 board released during the 3xxx series. It’s one a prebuilt and they just really cheated out on the motherboard. First thing were replacing in my wife’s build.

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AM5 gives you the best chance. lga1700 is a dead socket.
You need to get the right kit, and the right motherboard to get decent speed out of 128GB or 192GB. e.g. I don’t see any asus board can run 128GB over 6000.

128gb 6400
128gb 64001088×772 140 KB

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Do you know of a good place I could find info on what mobo’s would work? Honestly, for what I need, all I care about it 4 slot spacing between GPUs and either 10GB Ethernet or a USB4/TB3/4 port so I can use a 10gig adapter.

From looking around only Asus seems to make am5 motherboards right 4 slot spacing. Sadly even the ProArt which I like has 3 slot spacing and I’d have to do something like the Asus ROG Crosshair X670E for 4 slot spacing.

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Right now, only Asus has the option for 4 slot spacing.
All boards can do 128GB or 192GB, the problem is the speed supported, as current Ryzen 7000 only officially support 2DPC 2R at 3600MT/s.
If you can wait, just hold on for Zen5 release. AMD just rolled out AGESA 1.1.7.0 which officially support Zen5 CPUs. I expect Zen 5 will hit the market within 3 months.

BTW, 64GB udimm is coming. You will be able to buy 2x64GB kit very soon.

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PCIe riser might help with the spacing.