Register for the iXsystems Community to get an ad-free experience and exclusive discounts in our eBay Store.

Cool hardware: Addonics AD3M2SPX4 M.2 to PCIe converter

Western Digital Drives - The Preferred Drives of FreeNAS and TrueNAS CORE
Status
Not open for further replies.

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
12,904
I was a bit bothered by the large number of available SATA ports and one or two free PCIe slots in the VM storage server here. With the boost from 64GB to 128GB of RAM, the 256GB M.2 Samsung XP941 with its AHCI interface for L2ARC was feeling a little dated anyways.

M.2 offers several interfaces to the host. Electrically, it can offer SATA or PCIe. The SATA is clearly a bit of a legacy hack in order to allow M.2 to be adopted more easily into first generation laptops. PCIe provides direct attachment from the flash controller to the host PCIe lanes, and can be either AHCI (essentially SATA protocol and commands run over the PCIe bus) or the newer, made-for-flash NVMe.

The real problem with any storage server is that sooner or later you want to add "more". And Addonics happened to have a very unusual card: it provides an M.2-to-PCIe interface, like several other adapters, but it ALSO provides power to two more M.2-to-SATA adapters on the same board. Three M.2 SSD's on a single board (two of which have to be plugged into SATA).



Front side of card, with two 500GB Samsung 850 EVO's. These two slots connect directly to the SATA ports directly adjacent.



Rear of card, with a 512GB Samsung 950 PRO.

We bought two cards right away but I held off on populating the second card because this is mostly for experimentation at this point.

I think what I'm going to try is creating a nice SSD datastore out of the 850 EVO's, and using the 950 for L2ARC. I may follow up to this thread as things develop.

2020/10: Additional note: The Addonics has become hard to find but Startech also sells the same exact card as PEXM2SAT32N1
 
Last edited:

Jailer

Not strong, but bad
Joined
Sep 12, 2014
Messages
4,392
Just so I'm understanding this correctly, the m.2 cards do not have to be cabled to a SATA port to function, all three drives communicate via the PCIe slot correct?

That's a pretty slick card for $26.
 

Ericloewe

Not-very-passive-but-aggressive
Moderator
Joined
Feb 15, 2014
Messages
16,761
Just so I'm understanding this correctly, the m.2 cards do not have to be cabled to a SATA port to function, all three drives communicate via the PCIe slot correct?

That's a pretty slick card for $26.
Judging by the product page, it just routes 4x PCI-e to one side and the two other M.2 slots are fed by the SATA connectors.
 

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
12,904
Just so I'm understanding this correctly, the m.2 cards do not have to be cabled to a SATA port to function, all three drives communicate via the PCIe slot correct?
No, they're all powered by the PCIe, but the two SATA cards still need a system SATA port (or HBA port), which is the purpose of the SATA connectors.

The usual trouble for "guys like us" (waves arm around the room) is that mounting and cabling lots of devices in your system starts to get tricky at some point.

The VM filer here is pretty cool, but it isn't actually totally awesome. 24 2.5" HDD's giving 7TB of moderately fast datastore. For what goes on around here 97% of the time, it is a very good solution, not too expensive but big enough to move fairly fast under load. So when I look at the system inventory, I see that there's 10 SATA on the mainboard, two of which are taken by the SATA-DOM, two of which are taken by the rear SATA bays, leaving six SATA ports available. Then the HBA uses one SFF8087 to connect to the SAS expander backplane, leaving four lanes available on the other SFF8087. So that's like ten wasted SATA/SAS ports sitting idle.

If I'm going to add a card in to get an M.2 slot for an NVMe card for L2ARC anyways, then why not USE some of those idle SATA ports for something useful? I figure I can get up to 10 500GB Samsung 850 EVO's in there. If I do that, and I do them as three-way mirrors, it means I get a 1.5TB SSD datastore with a hot spare. I can't do that entirely with the Addonics card, but I can get four SATA M.2's in there that way, so that's a start. ;-)
 

Fuganater

Senior Member
Joined
Sep 28, 2015
Messages
474
Do report how it works. I am actually thinking of getting one for these instead of the SC846 drive tray that mounts to the side.
 

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
12,904
Seems fine. Things to know:

1) The PCIe M.2 SSD mounts on the back so it is technically hanging just a tiny bit within the next cardslot's space. This didn't turn out to be problematic even with an Intel 750.

2) There are some halfway decent activity LED's on the backplate.

3) The backplate is not vented. This is annoying for use in a server.

4) There's obviously no good way to heatsink the M.2 SSD's.

5) It does not feel like a super-high-quality part. It is run-of-the-mill PC gear quality IMO. The little post-and-screw assemblies make me nervous; they probably have some RTV silicone in their future just because I get this feeling that they could vibe loose.

But that 950 Pro, that sucker's a beast. Read/write speeds of at *least* 1.5GBytes/sec. Holy mackerel. The 850 EVO's are a lot more meh, being limited to SATA speeds.
 

Fuganater

Senior Member
Joined
Sep 28, 2015
Messages
474
So the 950 Pro is going through the PCI-I connector right?

What about using one of these for a standard SSD? Would speeds be better than via SATA? Or one of these for a single M.2 SSD
 

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
12,904
So the 950 Pro is going through the PCI-I connector right?
EINSUFFCOFFEE

What's a PCI-I connector? Mean PCIe? Yes, w.r.t. the 950 Pro, the board is a simple adapter that holds the NVMe M.2 and connects it electrically to the PCIe.

What about using one of these for a standard SSD? Would speeds be better than via SATA?
No, it's just a two port SATA controller that happens to also have some screw holes onboard to hold a SATA SSD. I don't see anywhere that it says what SATA controller chip is used, so I'd assume Marvell, which means that it isn't particularly desirable.

Or one of these for a single M.2 SSD
Yes, but for about the same price you can get the card I got and have the flexibility of two more M.2 devices. If you're looking for a single M.2 SSD-to-PCIe holder, the one I'd endorse is the Bplus M2P4A which comes with a heatsink for the M.2 card. That's what we got for the XP941 that had previously been in the VM server.
 

Fuganater

Senior Member
Joined
Sep 28, 2015
Messages
474
EINSUFFCOFFEEWhat's a PCI-I connector? Mean PCIe? Yes, w.r.t. the 950 Pro, the board is a simple adapter that holds the NVMe M.2 and connects it electrically to the PCIe.
Ya ya you know what I mean.

Yes, but for about the same price you can get the card I got and have the flexibility of two more M.2 devices. If you're looking for a single M.2 SSD-to-PCIe holder, the one I'd endorse is the Bplus M2P4A which comes with a heatsink for the M.2 card. That's what we got for the XP941 that had previously been in the VM server.
Do you think this is overkill for for a jail mirror?
 

Ericloewe

Not-very-passive-but-aggressive
Moderator
Joined
Feb 15, 2014
Messages
16,761
No, it's just a two port SATA controller that happens to also have some screw holes onboard to hold a SATA SSD. I don't see anywhere that it says what SATA controller chip is used, so I'd assume Marvell, which means that it isn't particularly desirable.
My guess is that it's one of the early Marvell 6Gb/s controllers. The ones slower than Intel SATA 3Gb/s. The 2TB drive size limit hints at that.
 

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
12,904
Though that could just be a recognition that the largest consumer SSD out there today is 2TB.
 

Fuganater

Senior Member
Joined
Sep 28, 2015
Messages
474
It was a dumb question, like asking "is my car fast enough?" hehehehe

:p
I found a cheaper one that has a heatsink for 1 M.2 drive. I'm going to see if I can find one for 2 of them. If not, 1 each works just fine.
 

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
12,904
Bplus makes the M2S4C holder for M.2 SATA that holds two or four.
 
Status
Not open for further replies.
Top