NVMe U.3 Backplane / solution


I am looking to use 15 x Micron 9400 Pro in the HL15, is there a way to get a u.3 compatible backplane? Or other solutions?

I have a broadcom megaraid 9670w-16.

Thank you!

Welcome to the community @Cpsv, it’s great to have you here!

Is the Micron 9400 Pro not just a SAS drive? The backplane that comes in the HL15 is a SAS/SATA backplate that can be used with either drive. To get the speeds to take advantage of that you will just need to make sure the HBA you are getting supports SAS drives. If you order a system you will just need to make sure you get 2 SFF-8654 cables for the Broadcom Megaraid 9670W-16i.

I am unsure if you can get a slimline SFF-8654 to SFF-8654 cable to work with your existing RAID card that you have however.

Nope they’re a 15mm U.3 drive which is not easily compatible with a HL15.

I don’t think the Stornado F2 will work either although you could ask 45Drives.

Ahh I see. Well with how new U.3 is right now, I am not sure it’s something that many Homelabbers will seek to install in their servers. I feel that most of the guys here are going to be looking for higher density with HDDs rather than faster SSD storage.

Maybe in the future this will become an option but I don’t even think any of the larger products are even built with U.3 compatibility.

Normally this kind of tech has a bit of a “Trickle Down” effect where as it get adopted to the enterprise solutions it will slowly work it’s way to the commercial market and finally to the consumer market. As it’s just now in the early stages of enterprise adoption, I think it will be a long while before products like the HL15 adopt this technology.

I didn’t know about this and I have been doing some research. I learned something new today!

TLDR: Don’t hold your breath for U.3 compatibility any time soon for the HL15.

There’s also U.2 and I’m going to be reworking the rear-mounted bracket 45Drives published as an STL to support both 15mm drives and hopefully six drives, then connecting 6x 6.4TB NVME with U.2 to my system through MCIO ports on the H13SSL-N.

Have the drives in hand. Have the first HL15 showing up tomorrow so will report back soon!

I suspect if you don’t mind the U.3 not being a proper backplane setup you could do similar — just an exercise in how much I can cram into the case above and around the mainboard.

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Thank you all!

This is very sad, the U.3 drives are becoming cheaper and cheaper, to build a backplane compatible with SATA/SAS/NVMe would make the HL one of the most desired cases for remote AI engineers.

I will have to find another Case or try some interesting solution, but I am surely not going to give up on my 15 drives.

For the custom solution, I thought of removing the backplane and routing cables directly from the RaidController, but I can’t find a nice caddy to hold the drives there and not impede the airflow too much, any suggestions?

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Honestly, after all the time and money into a project like that - don’t you think that it would just be a better use of recourses to just buy a barebones supermicro server and use something that is designed for those drives?


Because I can’t put a Supermicro Server in the room where I am working.

HL15 seemed to have quite good airflow and low noise.

Trust me, I would really love to buy a server from Supermicro if it would be reasonable, but I already have an Epyc Genoa 9554 and some other things.

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This noise thing is quite a showstopper, I find it interesting that many of my options got veto’d out by this requirement. My cluster runs in my closet, next to my desk, at home. Airplane jet engine sounds are a no go :smiley:

Though I feel that I should also be picky re: power consumption, as well as airflow.

Also my dog deciding to chew on wires (he ate my Cat 6A cable), and my 6 years old getting curious about all the lights…

Hi @SpringerSpaniel, we currently do not have any systems that support U.3.

Our Stornato F2 will be our first U.3 system but that is still in the making and the testing phase.

At this time we are unsure if we will be offering the U.3 backplane for the HL15, but we are working hard to get the U.3 backplane designed and made for the F2 so it might become possible in the future



It would be great to have a U.3 backplane that could be purchased, for such a good case would be such a pity to have support only for Sata and SAS 3… I am more than sure that many users would be thrilled to make combo setups, like NVMe + HDD, or U.2 / U.3 + HDD’s.

I remember how excited the creators and YT community were when Synology added SSDs into their NAS, but I also remember the disappointment of that being used for caching only.

The case is really really good, but with current features, it will definitely stick to a market smaller than it potentially could have.

Honestly I think the best option for the HL15 would be a hybrid drive bay area like some of the other units have, where maybe there are 4-8 slots over on the left for tri-mode (SATA/SAS/NVMe), then the right side has 8 slots for HDD (I don’t know what the allocation is in the hybrid bay options from 45Drives, but basically that).

That way the more expensive / harder to design high speed interconnects for U.3/NVMe could be focused on a few 2.5" bays on the left, and the normal SATA/SAS HDDs would go on the right.

Though in general, having a swappable backplane that could be upgraded for an even more premium setup (like 20 or 30 2.5" drives) would be pretty awesome!


@Cpsv I think its worth keeping in mind, 15 x NVMe is not in the budget of most homelabbers (those falling prices are still relative), and thats who the HL15 is targetted at. As an optional backplane upgrade in the future, that would be fantastic, but honesly the user base at this stage is us poor plebs who can only afford SATA… or SAS if you’re real fancy! :stuck_out_tongue_closed_eyes:

I think @geerlingguy nailed it. A hybrid option is probably a more appropriate, and attainable first step.

Out of curiosty though, I just priced 15 x 7.6TB 9400 Pros… that’s $37500 in my end of the world dollars (Australia), or converts to ~$24000 USD. :exploding_head:


Just wondering, as it’s been a while — have you had a go at making the 3D prints work for 15mm drives yet?

I am going to try installing a couple U.2 drives in my system, and right now I don’t have a good way of getting them in there. I did a print then realized the drive bays are for narrower SSDs. Instead of duplicating effort, I’d rather just use yours and link to it eventually when I talk about it in a video!

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I wound up using @Venson’s design—see 15mm SSD Mounting Bracket? - #15 by geerlingguy

That, plus a $28.88 DiliVing SlimSAS to U.2 cable (Amazon link: https://amzn.to/3QuD6B2), seems to get me two working drives.

Power was a little sketchy—I didn’t have a molex power splitter, so I just yanked one from the power midplane and connected it to the molex 4-pin power input on that DiliVing cable.

I ordered a StarTech.com molex Y-splitter and will use that once it arrives. Shouldn’t be an issue as I don’t think the midplane routes each 4-pin connection to individual pins on its backplane power cable. I think they’re all in parallel?