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Finding a PCIe M.2 (2x M-key) adapter that runs two NVMe modules

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backintime

Registered
Joined
Sep 30, 2020
Hi guys!

I kind of discussed this question off-topic already in another thread at the Video Cards section earlier today, but I'm pretty much stuck, so I thought it would be better to open up a separate thread.

CPU: AMD Ryzen 9 5950X
MOBO: ASUS ROG Crosshair VIII Dark Hero (manual)
STORAGE: Samsung 980 PRO 1 TB, Samsung 960 EVO 1 TB, Samsung 960 EVO 500 GB, Samsung 960 EVO 500 GB

I have four NVMe M.2 modules, which I like to run on my new ASUS Dark Hero motherboard. However, the board has only two M.2 slots. At first I thought about buying the HYPER M.2 X16 GEN 4 CARD (manual), which allows you to extend with four extra NVMe's. The issue however, is that it only runs four of them, when installed in PCIe slot 1.

This basically leaves me with the alternative: Installing two NVMe's on the motherboard and using an adapter for the remaining ones in PCIe slot 3.

Issue
I found out that there are two types of M.2 slots on these 'dual M.2 adapters': M-key and B-key. The M-key being for high speed NVMe's, the B-key for slower SSD's. A LOT of these cards only allow you to install one NVMe module. If there are two M.2 slots, then it's usually to combine one NVMe module with a slower SSD module.

If it weren't for this M-key/B-key thing, this card would be just great. Also in terms of looks... Some of these cards are fully red or old school green or just ugly: https://www.amazon.com/Adapter-advanced-solution-Controller-Expansion/dp/B07JKH5VTL

HYPER M.2 X16 GEN 4 CARD
When I look back at the ASUS Hyper Card, it seems like all four M.2 slots are from the type M-key. Which basically is a nice solution, however: It has a fan and I don't know what effect this x4 x4 x4 x4 card will have on the performance of the rest of the system (GPU in slot 1 for example). I'm a newbie in terms of the technicals, so I did my best to find an answers online, but I couldn't really narrow things down to what I needed to know. From what I understand it should be fine as long as I would be running only two modules on this card? Besides a GPU in slot 1?

The 'overkill' ASUS Hyper GEN 4 Card would be a nice solution, but like I said: It would be great if I could get a card which uses a heatsink instead of a fan.

The thing is though... the dual M-key M.2 adapter cards that I'm able to find are a more expensive than the 'more simpler' ASUS Hyper GEN 4 Card. Most of the M-key AND B-key adapter cards are cheap. Varying from $10-50. The 2x M-key adapter cards seem to be jumping from $150 up to $600. While the ASUS Card is around $85.

Am I missing something here? Is there an easier name for the card that I'm looking for? Do I have to face the fact that I'm stuck with a fan since NVMe's produce more heat? You would think that there are cheaper 2x M-key M.2 adapter cards. I mean... the ASUS Card has 4 slots that run at x4 and are all M-key. It costs $85. Why would a more simpeler brand charge way more for only two M-key slots?

I hope I was being clear enough 😁

Thanks!
 

Ben333

Folding for Team 32!
Joined
Feb 18, 2007
The one you linked, I think supports one nvme directly over PCIE and then one M.2 via the sata plug... not sure but that is what it looks like to me.

https://www.amazon.com/Supermicro-AOC-SLG3-2M2-PCIe-Add-Card/dp/B071S3ZY8P <-- This may be what you are looking for.

Also here for just over 20 bucks, and in black soldermask: https://www.amazon.com/EZDIY-FAB-M-2-PCIE-Adapter-Supports/dp/B086W5VLQ9 (this one uses a mini-riser \ cable in order to run two NVME drives using only the narrow slots)

Last but not least, a single nvme to 4x adapter... only $14... just buy two? If you have the slots available. https://www.amazon.com/Rivo-PCI-Riser-Express-Adapter/dp/B0773ZR6L8
 
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backintime

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Sep 30, 2020
Hi, thank you again for your comment!

The one you linked, I think supports one nvme directly over PCIE and then one M.2 via the sata plug... not sure but that is what it looks like to me.

I'm not sure. You mean you think the B-key (SSD) slot might function as an M-key (NVMe) slot once it is powered externally? I mean... if you look at the 'pattern' of the connectors on the board itself, you can see that an M-key M.2 module (NVMe) won't physically fit a B-key slot. Or am I seeing this wrong? ;)


Clicking on this link doesn't show me the model you're referring to. The Supermicro from the URL? When I Google it, it seems like it doesn't have any heat control at all. The modules are just wide open on the card with no heat sinks or fan. Another Amazon link to the same card shows that you can basically buy separate heat sinks which can be attached to the card with a rubber band?: amazon.ae/Supermicro-AOC-SLG3-2M2-PCIe-Add-Card/dp/B071S3ZY8P

Also here for just over 20 bucks, and in black soldermask: https://www.amazon.com/EZDIY-FAB-M-2-PCIE-Adapter-Supports/dp/B086W5VLQ9 (this one uses a mini-riser \ cable in order to run two NVME drives using only the narrow slots)

This seems interesting! This mini-riser... is that supposed to go into PCIe slot 2? Meaning, Slot 1: GPU, Slot 2: Riser, Slot 3: M.2 card?

Last but not least, a single nvme to 4x adapter... only $14... just buy two? If you have the slots available. https://www.amazon.com/Rivo-PCI-Riser-Express-Adapter/dp/B0773ZR6L8

I'm not really sure if a second card in slot 2 (right beneath the thick GPU) would 'fit'. If it doesn't block any fans, so to speak. I haven't been able to build it yet. If one of the two dual options given above work, I probably will stick with one of those :D

Thanks again!
 

EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
You want M-key m.2 AIC. Your SATA based and PCIe NVMe m.2 modules both use M-key.

The issue however, is that it only runs four of them, when installed in PCIe slot 1.
Sort of. :)

You can install that in slot 1 and get the full bandwidth (assuming nothing is using slot 2), or put it in the second slot and get half kf that bandwidth (plenty for 2x NVMe based m.2 storage). Or it can go in the 3rd slot (which would provide enough bandwidth for 2x 3.0 x4 NVMe based m.2 storage). You're running two from the aic, right? 2 on the board, two on the aic?

Note that you want a PCIe 4.0 add in card if you're putting any pcie 4.0 based drives on it.

We've already talked about the performance losses you'll receive in the other thread...you DO know how much it will lose... I gave you a link, in fact.
 
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backintime

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Sep 30, 2020
Hi @EarthDog, thanks again!

I think I might have focussed too much on the PCIe-card-in-slot-1-thing in my message above. Going with what you guys have said here and before, I think it's better to go with a separate (non-ASUS Hyper) card which holds two NVMe drives. Like discussed with @Ben333 above.

Right before you posted your message, I was going to go with:

1x Supermicro AOC-SLG3-2M2-O (PCIe 3.0 x8 to install 2x Samsung 960 EVO 500 GB PCIe 3.0 x4)
2x Thermal Grizzly M.2 SSD Cooler (same brand as CPU Thermal Paste)

From what I understand, the Supermicro card is a 'M-key m.2 AIC', right? :)

The second option given by @Ben333 was the EZDIY-FAB Dual M.2 PCIE Adapter. This one looks a little nicer, but it holds up two PCIe slots. In that sense, the Supermicro sounds more interesting as it only holds one slot.
 
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EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
I didn't look at his options in detail, though I saw one of them had two possible connections to a PCIe slot. How that works, no idea. I don't know if it is an 'option' to use or if both are required. Seems overly complicated, honestly.... but I'm not sure how that card works so it might be me, lol.

As far as the Supermico card being M-Key, yes - https://www.supermicro.com/en/products/accessories/addon/AOC-SLG3-2M2.php
 
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backintime

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Sep 30, 2020
@EarthDog Thanks!

I see you removed your edit, which I was trying to find more information about. The possibility that these two NVMe drives might run slower on the Supermicro card because it runs on one PCIe slot, compared to the other one with the riser cable, connecting to a second PCIe slot.

Is that still the case?

This might be a stupid thought/question, but the Supermicro card being x8 and the 3rd PCIe slot also being x8... wouldn't that mean it could run two x4 NVMe cards without any hick ups? Or is that like I said... a stupid thought? 😜

If you had to choose, you would probably go with the EZDIY-FAB Dual M.2 PCIE Adapter which connects to a second PCIe slot?

Thanks again!

Edit: Okay, wait... I think I'm mixing up the speeds of the PCIe's on the motherboard again. The 3rd slot is x4, I think. The second one is x8. The manual (page 1-9) also says two x4's should be run at PCIe slot 2?

Expansion Slots

2 x PCIe 4.0 x16 (x16 or dual x8)
2 x PCIe 3.0 x16 (x16 or dual x8)
1 x PCIe 3.0 x16 (x8 mode)
AMD X570 chipset
1 x PCIe 4.0 x16
1 x PCIe 4.0 x1
AMD Ryzen™ 5000 Series/ 3000 Series Desktop Processors
AMD RyzenTM 4000 G-Series / 2000 Series Processors
AMD RyzenTM 3000 G-Series / 2000 G-Series Processors
 
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EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
I wasn't sure on the edit. The PCIe 'teeth' show x8 so you likely get x4 for each on that.

The third slot is PCIe 4.0 x4 which is 2x PCIe 3.0 x4. It should be able to run full out on there, I believe.

The breakdown is as follows according to your manual (ignoring the x1 slot)...

2 x PCIe 4.0 x16 (x16 or dual x8 - CPU)
1 x PCIe 4.0 x16 (x4 mode - chipset)

...in this case x16 refers to the size (full-length slots) and in parenthesis is the bandwidth and source.

EDIT:
The manual (page 1-9) also says two x4's should be run at PCIe slot 2?
The manual is confusing. It is listing support for the different processors. The APUs have less lanes available... ;)
 
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backintime

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Sep 30, 2020
The manual is confusing. It is listing support for the different processors. The APUs have less lanes available... ;)

I'm glad it wasn't just me getting insane 😁
The Expension Slot list is from the official motherboard website by the way: https://rog.asus.com/us/motherboards/rog-crosshair/rog-crosshair-viii-dark-hero-model/spec/

Okay... so if I understand things correctly, I should be fine with buying/trying the Supermicro card? If it does turn out to be slower, I can always change to the EZDIY-FAB Dual M.2 PCIE Adapter which connects to two PCIe slots.

If that's the case, I think this case is finally solved 😜
 

habbajabba

Member
Joined
Oct 29, 2005
Location
Oregon
Your board has the newer PCIe Gen4 interface. You need a Gen4 expansion card and new nvme's if your current ssd's aren't Gen4's. That 980's a start.
Asus card $70 supports 4 gen4 nvme's
https://www.amazon.com/ASUS-M-2-X16-Expansion-Card/dp/B084HMHGSP
There's other options I'm sure but putting those 960evo's in is ridiculous when the gen4 nvme's would be at least twice as fast. Don't waste your time on a gen3 card or any older nvme's. The Gen4 PCIe interface blows gen3 all to hell.
Nice board. I like amd over nvdia myself. I just want to to see some 5GHz cpu's. Their latest and greatest are not as fast as I'd like, if you know what I mean.:D
4 1TB nvme's would be really expensive but totally worth it in the long run (raid?). For $400 (~3TB nvme) one can get like 12TB of sata, really a much better option just for saving stuff, at least on my budget.
 
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