Any LGA1700 motherboards with x4x4x4x4 bifurcation?

I have an Intel 12600K that I want to use for a small NAS, and my plan was to use an Asus Hyper M.2 Gen 4 card to add in 4 NVMe SSD’s to use in a ZFS RAIDz1 pool.

I initially went with an Asus Prime Z690M D4 board since I already have 64GB of DDR4 RAM on hand (and DDR5 is still quite expensive for not much gain).
I also went with an mATX board since I already have a case that only supports mATX or smaller, and I only needed the top PCIe slot to work in x16 (x4x4x4x4) and a second PCIe slot to work in x4 mode.

I made the mistake of not checking for PCIe bifurcation compatibility, as I found out later that this board only supports bifurcating the top PCIe x16 slot into x8x8 mode, which would only allow for two of the 4 drives to work in the system. I missed this page which lists out how many drives can work on any given system, and saw that Asus’ Z690 boards only support 2 drives through this adapter card: [Motherboard] Compatibility of PCIE bifurcation between Hyper M.2 series Cards and Add-On Graphic Cards | Official Support | ASUS Global

I’ve tried looking for other boards from other manufacturers, but none of them specify if they support PCIE Gen 4 x4x4x4x4 bifurcation.

So my question is this: are there any Z690 or even B660 mATX boards that have PCIe Gen 4 x4x4x4x4 bifurcation in the top PCIe x16 slot?

I’m even willing to get a full ATX motherboard and getting a new case if such a board exists, I jsut can’t find any specifics online

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I made the same mistake when investing in the Hyper M.2, so it’s currently sitting on a shelf.

That said, I bookmarked a review I saw in case I decided to revisit bifurcation:

This uses an IOCREST card with a switch on it. Not true bifurcation, but might do in a pinch if you don’t find any other suitable options. Also note it’s also PCIe 3 not 4.

Yeah problem is I’d want a PCIe 4.0 card, I wouldn’t mind having to get something to replace the Asus Hyper M.2 Gen 4 card as long as it’s not wildly too expensive.

I did find this Sonnet card that specifically says it doesn’t need PCIe bifurcation
support, but it’s also only PCIE 3.0 and costs $400 USD: Sonnet M.2 NVMe SSD 4x4 PCIe Card (Silent) – Sonnet Online Store

Also found this one that specifically says this model does not require bifurcation, but just like the Sonnet one it only does PCIe 3.0 speeds and is still quite expensive at $300 USD: https://www.amazon.com/GLOTRENDS-Non-Bifurcation-Motherboard-Bandwidth-Aluminum/dp/B0847N8B5B

Did some research a couple of months back, IIRC the Alder Lake CPUs are hardcoded for x8x8 bifurb, if bifurb is even allowed, so doesn’t look very bright. :frowning: Would love to be proven wrong on this though, but with that information in mind, your options are;

  1. Wait for Gen 13 and hope that has better support from the CPU
  2. Wait for AM5 and it’s X670 boards with DDR5 / PCIe 5.0 killer combo
  3. Get an AMD solution now

Since option 1 is probably not going to happen, 2 or 3 remain. The only difference, really, between the two is how many m.2 slots you want to add to your mATX motherboard. I have heard rumors of up to 6 m.2 slots on the motherboard in the next generation high end boards, and even the low-end will have at least 3x m.2 slots.

It would not surprise me if, in all honesty, AM6 will only come populated with something like 8 m.2 slots and a single x16 PCIe slot on many models - at least in the consumer space. But this is all conjecture and rumors at this point.

If you want to just run your stuff right now, my recommendation would be a AMD Ryzen 5 5600 CPU coupled with a Gigabyte Aorus B550M Elite board.

The only thing you will lose is the integrated graphics and the PCIe 5.0 lanes, which, well, are not needed once you’ve installed Linux and activated SSH - which can easily be done with a temporary graphics card in the fourth slot.

Of course, you will want to upgrade that combo in about 6-7 years or so. But by then the landscape will be completely different in either case.

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Supposedly w680 mobo can do this. But I can’t get my hands on one. And it might just be 2-2(from chipset) and not 4x4 from cpu.

So if anyone sees. W680 mobo for sale anywhere lmk

I wouldn’t count on that. He’s using mATX for the small NAS and small boards just don’t have the space. And I wouldn’t put 6 on-board slots in a RAID-like configuration if only for the inevitable chipset slots and corresponding bandwidth bottlenecks with NVMe.
I was expecting Intel to address this problem with the first PCIe 5.0 boards (well, because x16 5.0 slot is beyond overkill for any single device right now).

The only other option I see is an HBA like LSI 9500 series with Tri-mode. But these kind of things are expensive and can cause their own kind of headache from what I’ve heard. And you have to buy U.2 adapters and have space in the case to make those M.2 fly.

  1. Wait for Gen 13 and hope that has better support from the CPU
  2. Wait for AM5 and it’s X670 boards with DDR5 / PCIe 5.0 killer combo
  3. Get an AMD solution now

Problem is I already have the 12600K and the motherboard, and the only reason I wanted it is for to be able to access the BIOS and to have QuickSync encoding. I wouldn’t mind shelling out money for a motherboard that supported this type of bifurcation, or getting a card to replace the Asus Hyper M.2 Gen 4 card (posted 2 cards earlier that didn’t require bifurcation but they’re both PCIe 3.0).

Nu I’m not really trying to completely swap to a different platform entirely, and finding a board with a bunch of M.2 slots natively would be fine - but then I’d still have that PCIe x16 slot that won’t be used at all.

Supposedly w680 mobo can do this. But I can’t get my hands on one. And it might just be 2-2(from chipset) and not 4x4 from cpu.
So if anyone sees. W680 mobo for sale anywhere lmk

Ooohhhh didn’t even know this was a chipset that’s (supposed to be) out. I figure if you can’t find anything then it might be a paper launch where we might not see anything for quite a while.

The Supermicro W680 Board can be purchased at multiple german retailers: Supermicro W680 ab € 486,89 (2022) | Preisvergleich Geizhals Deutschland

More interested in the AsRock W680D4U-2L2T thought.

no bifuriation unfortunatly, just tested it.

on w680?

Damn that’s unfortunate if true.

My next silly idea is to find some PCIe 4.0 splitter that goes from x16 to two x8 slots so I can get some x8 to two NVMe M.2 adapters that don’t require bifurcation support

I know LSI has their 9500-16i cards and related models that support for M.2 drives in an x8 slot but not sure why that’s how they configured the cards to work

yes a supermicro X13SAE-F I wanted to run 4+ u.2 pcie 4.0 nvmes of it, but theres no bifurication options in bios. I thought this was standard now coming from mostly amd board

I was hoping to run a 12900ks with lots of nvmes but looks like this is not the best setup. could get a highpoint board but those are expensive(1k+ for the SSD7580A dont know if there are any cheaper alternatives?), or some pcie x4 to u2 adapters with some m.2-u.2 but not a very slick set up.

also 12900ks isnt even supported by the board i came to realize so I’am weighting my options now(it boots fine but clocks arnt right doing some more testing). will either wait for a asrock W680D4U-2L2T with oculink, although they go through the pch but not really an issue. or just get a consumer board.

I need the highest single core speeds possible along with fast low latency storage(optane too expensive still) thus the wierd server setup.

funny thing is i have a bunch of different cards/adapters for nvme. including a lsi 9400i, but they use those silly non standard nvme enabler cables that are 100$ each so i refuse to even try it. also its pcie 3.0. 9500 could work i guess if you wanna shell out for the overpriced nvme cables. but at that price might as well get the highpoint card.

u.2 nvme is such a headache for home servers. so many connectors and everyone uses different ones with slimsas 4i/8i, oculink 4i/8i and sff8643 and then even more annoying if you want 4.0 and the need for retimers in some setups. and then disk cages/cables that dont support 4.0 etc.

The Broadcom 9500 (better choice if NVMe-only: P411W-32P PCIe Switch HBA) uses standard SFF-8654 8i cables.

(-) HBA 9500: Doesn’t seem to work with NVMe Backplanes, only PCIe Gen4 x8 host interface
(+) HBA 9500: Also works with SATA and SAS drives

(+) P411W-32P: Works with backplanes, also PCIe Gen4
(+) P411W-32P: PCIe Gen4 x16 host interface
(-) P411W-32P: Around 20 W typical power draw

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thats a good option for sure, but no stock that i could find in europe

small update the 12900ks does work with the board after a bios update, board is only rated for 125w and the 12900ks seems to perform exactly like just a K CPU not hitting 5.5 single core, no avx512 it looks like either even after disabling e cores.

Not sure what this has to do with the topic at hand but ok

So I ended up giving the 12600K and motherboard to a friend who needed an upgrade from his 7700K. My plan is to wait for Ryzen 7000 and see what they have in terms of bifurcation so I can try to fit my Asus x16 to 4 NVME M.2 adapter in with all drives working.

I assume that X670 / X670E with Ryzen 7000, just like X570 with Ryzen 3000 / 5000, that I’ll only be able to run the 2nd PCIE x16 slot in PCIe 5.0 x8 and not be able to run it in PCIE 4.0 x16 mode, but a man can hope and dream.

Did you check if any Ryzen 7000 setup supports bifurcation into x16 → (x4 + x4 + x4 + x4) ?

In short, yes. ASUS has updated their list to include their ASUS branded X670 and B650 boards: [Motherboard] Compatibility of PCIE bifurcation between Hyper M.2 series Cards and Add-On Graphic Cards | Official Support | ASUS Global

The bad news is that the cheapest motherboard(s) that support this are still $300+.