Understand how this M.2 B+M Key SSD can work via PCIe Adapter Card with 2 slots (both 1 B and 1 M slot)


Understand how the M.2 B+M Key SSD can work via PCIe Adapter Card with 2 slots (both 1 B and 1 M slot)?

We recently bought a Sandisk SSD X400 M.2 (B+M Key) to do some sample tests, see how it works and are having issues. Details below.

Read these articles around B/ M key SSDs & slots and Sandisk datasheets etc, but still not clear:

We have a PCIe card (driver less/ transparent) that has 2 slots that support the following:

  • M key Slot – PCIe 3.0 x 4 (PCIe 2.0 Compatible)
  • B key Slot – SATA (6gbps)

Dell Vostro 230 + Windows 8.1

  • Intel Core i3 4150 @ 3.5 Ghz – Haswell 22nm
  • Motherboard: 0T1D10
  • BIOS: A06
  • Date 8/19/2014 (Probably needs to be updated – will do anyways)

We put the X400 in the M – key slot and cannot see any storage or indication of its availability.

  • Can it be used via a native M-key slot on a motherboard?
  • Can it be used (even as storage) on the M-key of the PCIe card or only B-key via SATA?
    (currently not trying to boot from it)
  • Can it be used later to boot via PCIe card – M and/ or B keys?
    (On another machine, assuming its BIOS supports booting from such)

PS: I'm thinking, even if BIOS support for PCIe booting is not there, shouldn't we be able to access the storage, atleast? Does it need special drivers in Win 8.1?

Best Answer

The datasheet indicates multiple times that this SSD only supports the SATA protocol. That of course also means it can be used in a (true) dual-personality M.2 slot. It won't work with PCIe, though.

According to my favorite price comparison website, SanDisk does not offer any M.2 SSD with PCIe connectivity.

The part of the datasheet you're referring to, in the right column of the first page, only has SATA highlighted.

According to Wikipedia, both B and M keyed connections offer native SATA connectivity, which is what this SSD requires.