M.2 slot uses PCI-E or Sata?

[Destynx]

Were building an unraid media server and vm machine and are nearly finished picking out components.

One of the last questions is, can we use all 10 Sata connectors when we are using the M.2 slot on this or this motherboard? (I know the difference in formfactor, still deciding on the case)

Tried to find some info on it but I'm not sure.

Someone who can give a clear explanation on the whole M.2 interface bus?

And in particular about those two boards. 

[deleted_member_030719]

There are PCIe M.2s (950 Pros) and there are sata M.2s (850 EVOs, MX300, etc.)

[Destynx]

We would be using the Samsung 960 Evo 256GB M.2 SSD in this build.

[deleted_member_030719]

4 minutes ago, Destynx said:

We would be using the Samsung 960 Evo 256GB M.2 SSD in this build.

PCI-e then.

[Randomguy1911]

11 minutes ago, Destynx said:

One of the last questions is, can we use all 10 Sata connectors when we are using the M.2 slot on this or this motherboard? (I know the difference in formfactor, still deciding on the case)

Tried to find some info on it but I'm not sure.

Asrock X99M Extreme4

Storage • 10 x SATA3 6.0 Gb/s Connectors
(S_SATA3_3 connector is shared with the eSATA port) 
(S_SATA3_2 connector is shared with Ultra M.2 Socket) 
So 10x Sata AND and M.2 is not possible.

 

MSI X99A RAIDER
* The SATA Express port or SATA5~6 ports will be unavailable when installing the M.2 SATA interface module in the M.2 port. ** Intel RST does not support PCIe M.2 

[Cereal5]

9 minutes ago, Jed M said:

PCI-e then.

Some motherboards M.2 slots use the SATA bus no matter what