# B450 M.2 device support



## Absolution (Nov 22, 2018)

Hi guys, 

Got myself a MSI B450M Mortar motherboard and it has 2 M.2 slots.

M2_1 supported by the CPU (in use)
M2_2 supported by the B450 chipset (empty)

The motherboard lists this as :






Does this mean I cannot use a SATA M.2 in M2_2?

How come the B450 chipset doesnt support the SATA interface over a M.2 slot?

Anyone knows? Would be nice to know before I buy another M.2 SATA SSD.


----------



## GoldenX (Nov 22, 2018)

It should work, but now you left me in doubt.
There's always the option of using an NVME SSD and call it a day.


----------



## Absolution (Nov 22, 2018)

1TB NVMe is for A$288 (samsung 970 evo)

1TB SATA is for A$199 (samsung 860 evo)

Also the NVMe would be under my GPU so I'd be concerned about temperatures anyway.

Kinda sucks how MSI designed that slot M2_2


----------



## GoldenX (Nov 22, 2018)

Does your card fan blow directly to the SSD?


----------



## EarthDog (Nov 22, 2018)

If it doesnt say SATA, it likely doesnt support it. Contact msi to confirm 100%.


----------



## FordGT90Concept (Nov 22, 2018)

M Key (which both are) supports PCI Express x4 (up to), SATA, and SMBus.  The only caveat you have to watch out for is M2_2 is electrically associated with PCI_E4 so both can't be populated simultaneously.



Absolution said:


> Kinda sucks how MSI designed that slot M2_2


AM4 doesn't expose very many PCI Express lanes to the motherboard.  All AM4 motherboards have similar limitations unless they put PCI Express bridge chips on the board.


----------



## EarthDog (Nov 22, 2018)

This would be the first time I've come across where if it's not mentioned in the manual SATA would be supported. At least on the intel side I'm more familiar with, the manuals are explicit about support... not all m.2 slots support both SATA and PCIe based modules in that world.

MSI is an AIB (all AIBs?) that mentions both when each are supported by the mobo (again, Intel).

Is it different in the amd world, how a company presents its information?


----------



## Vya Domus (Nov 22, 2018)

It'll work, change the slot if it doesn't. I believe the only limitation is that you can use no more than 1 nvme drive.



EarthDog said:


> Is it different in the amd world, how a company presents its information?



These manuals are not made by AMD or Intel. They can be lackluster in information on either sides.


----------



## londiste (Nov 22, 2018)

Absolution said:


> Does this mean I cannot use a SATA M.2 in M2_2?


Yes, exactly.


Vya Domus said:


> It'll work. I believe the only limitation is that you can use no more than 1 nvme drive.


No such limitation.


----------



## TheLostSwede (Nov 22, 2018)

Absolution said:


> Hi guys,
> 
> Got myself a MSI B450M Mortar motherboard and it has 2 M.2 slots.
> 
> ...



M.2 doesn't have to support SATA and in your case, it won't, as no SATA interface is routed to the slot. For some reason, MSI decided not to use the second SATA port built into the CPU. Could be a trace routing issue on the board. So the short answer is no, your second slot doesn't support SATA drives.


----------



## londiste (Nov 22, 2018)

TheLostSwede said:


> Could be a trace routing issue on the board. So the short answer is no, your second slot doesn't support SATA drives.


That is the most likely explanation here. MSI wanted another PCI-e slot (PCI_E4) on the board in case M2_2 is not used and these are routed over a simple switch.
CPU only has 16+4+4 PCI-e lanes where 4 are going to chipset and 16 for the GPU, so they cannot get another M2 slot directly out of CPU either.


----------



## Vya Domus (Nov 22, 2018)

Here's an idea, why not just put your current SATA SSD into the slot and see if it works ?



londiste said:


> No such limitation.



Effectively there is, you would want to use the slot that supports PCIe 3.0 x4.


----------



## londiste (Nov 22, 2018)

A little more trust into manufacturers' specifications 



Vya Domus said:


> Effectively there is, you would want to use the slot that supports PCIe 3.0 x4.


Oh, you are right. Forgot about the PCI-e 2.0 in there. 

Its "nice" that you have a choice of using a SATA M.2 drive and a somewhat bottlenecked NVME drive or a NVME drive as it is supposed to be and no SATA.
That's almost as evil as mITX boards with two M.2 slots... where the PCIe-only slot is in the back... good luck cooling that, especially compared to the slot in front with a heatsink on it


----------



## EarthDog (Nov 23, 2018)

Vya Domus said:


> It'll work, change the slot if it doesn't. I believe the only limitation is that you can use no more than 1 nvme drive.
> 
> 
> 
> These manuals are not made by AMD or Intel. They can be lackluster in information on either sides.


If it doesnt say sata, I wouldn't bet on it.

I know they arent made by intel or amd. What I wrote was suggesting that perhaps AIBs write it different for AMD hardware (the line above was taking AIBs). As I said, at least for intel boards, they EXPLICITY LIST SUPPORT. If it doesnt say sata, chances are infinitely greater the slot doesnt support it. It's just that simple (for intel...I dont know amd well and why i asked if aib write it different).



londiste said:


> good luck cooling that, especially compared to the slot in front with a heatsink on it


the one that shares its heatsink with the pch typically and right above the gpu??? Not sure which would be better... it would literally be a case by case basis.


----------



## FordGT90Concept (Nov 23, 2018)

M.2 M-key requires PCIE x4, SATA, and SMBus support.  Manufacturers only say if there's exceptions to that rule.  In this case...
M2_1 doesn't support SMBus: PCIe 3.0 x4, SATA
M2_2 is PCIe 2.0 instead of PCIe 3.0: PCIe 2.0 x4, SATA, SMBus (will disable PCI_E4)

I would install a SATA M.2 device to M2_2 because it's much lower bandwidth.



M.3 will be PCIe NVMe only.




Absolution said:


> 1TB NVMe is for A$288 (samsung 970 evo)
> 
> 1TB SATA is for A$199 (samsung 860 evo)
> 
> ...


I definitely recommend going NVMe.  That price is kind of ridiculous though.  See if you can buy an NVMe from a different manufacturer (e.g. Kingston Digital or Crucial)

NVMe should theoretically run cooler than SATA because the controller on the chip is simpler.  Then again, NVMe gets a lot more performance out of the memory chips which may translate to more heat.  Might be a wash.


----------



## EarthDog (Nov 23, 2018)

FordGT90Concept said:


> Manufacturers only say if there's exceptions to that rule. In this case...


Across nearly 3 dozen boards I've reviewed, for both x299 and z370, I've seen it mention explicit support. Examples....

From the z370 taichi manual....

2 x Ultra M.2 Sockets (M2_1 and M2_2), support M Key
type 2242/2260/2280/22110 M.2 SATA3 6.0 Gb/s module
and M.2 PCI Express module up to Gen3 x4 (32 Gb/s)**
•     1 x Ultra M.2 Socket (M2_3), supports M Key type
2242/2260/2280 M.2 SATA3 6.0 Gb/s module and M.2 PCI
Express module up to Gen3 x4 (32 Gb/s)**

From asus z370-f....

1 x M.2_1 Socket 3 with M key, type 2242/2260/2280 storage devices
support (both SATA & PCIE 3.0 x 4 modes)*
- 1 x M.2_2 Socket 3 with M key, type 2242/2260/2280 storage devices
support (PCIE 3.0 x 4 mode)**

Msi z370 gaming pro carbon...

2x M.2 slots (Key M)
Support up to PCIe 3.0 x4 and SATA 6Gb/s

Giga z370 aorus gaming 5...

2 x M.2 connectors (Socket 3, M key, type 2242/2260/2280/22110 SATA and
PCIe x4/x2 SSD support) (M2M_32G, M2A_32G)
- 1 x M.2 connector (Socket 3, M key, type 2242/2260/2280 PCIe x4/x2 SSD
support) (M2P_32G)


I picked one board from the 4 big boys. All show both sata and pcie when the slot supports both. If sata isnt listed, chance are it isnt supported.

Nvme based m.2 drives typically run hotter than sata drives. There are articles all over showing this. I dont recall any being sata.



Edit: from wiki...

Computer bus interfaces provided through the M.2 connector are PCI Express 3.0 (up to four lanes), Serial ATA 3.0, and USB 3.0 (a single logical port for each of the latter two). *It is up to the manufacturer of the M.2 host or device to select which interfaces are to be supported, depending on the desired level of host support and device type. *


----------



## FordGT90Concept (Nov 23, 2018)

I would caution that MSI doesn't say anything about NVMe yet I just put one together an B450M Pro-M2 with an NVMe drive and it works fine.

AMD has not published anything that says what B450 M.2 supports.

Honestly, the simplest way to be certain is to contact MSI tech support.  They can check with engineering to give a definitive answer if you're unable to test.


----------



## EarthDog (Nov 23, 2018)

Yep.. said that at post 5 to contact msi. 

Nothing mentions "nvme"... its "pcie" that all the manuals mention.... just like the b450 above.

Cant say I've run across a sata only m.2 slot..  but believe it could exist.

The bottom line is, at least for intel (and likely amd), if it doesnt mention it, it likely wont support it.


----------



## FordGT90Concept (Nov 23, 2018)

If you only went by what the manual said, you'd be convinced NVMe only works in conjunction with RAID0 or RAID1.


----------



## EarthDog (Nov 23, 2018)

That isnt how it reads, but t ok...


----------



## Deleted member 67555 (Nov 23, 2018)

I have both M.2 slots on my Z370 board filled and after I filled the lower M.2 slot I lost PCI-E slots.
As far as I understand it doesn't matter what type it is the only thing that matters is if the slot is being used and when it is I lose it.
EDIT:
None of my post was correct..
I originally said it was SATA ports that were lost but I meant PCI-E but got stuck on SATA ports.


----------



## FordGT90Concept (Nov 23, 2018)

My motherboard has caveats for SATA Express/SATA ports shared with the M.2.  Can only use either or, not both.  It's quite common because, especially low end CPUs don't expose many lanes.


----------



## Absolution (Dec 4, 2018)

Meh ended up getting a SATA Samsung 860 2.5" form factor

Will ask on MSI forums though to be sure. M.2s were hard finds anyway.

Also anyone who comes across this page because of B450M Mortar, the board doesnt support addressable RGB ( no header ).


----------

