RE: Dell XPS 13 2015 and Samsung 950 PRO m2 Upgrade
I was looking into buying that card for my Dell XPS 13, seeing the manual of the 9343 it says SATA nothing about the PCIe, so doesn't seem like it is going to work.
Not sure if a BIOS update would enable this as it seems to depend on the controller onboard of the motherboard, the 9350 seems to have both controllers.
M.2 is the physical form factor. SATA and PCIe refer to the storage interface, the primary difference is performance and the protocol (language) spoken by the M.2 SSD.
The M.2 spec was designed to accommodate both a SATA and PCIe interface for SSDs. M.2 SATA SSDs will use the same controller currently on typical 2.5 in SATA SSDs. M.2 PCIe SSDs will use a controller specifically designed to support the PCIe protocol.
An M.2 SSD can only support one protocol, but some systems have M.2 sockets that can support either SATA or PCIe.
Does an M.2 SSD support both SATA and PCIe?
No. An M.2 SSD will support either SATA or PCIe, but not both at the same time. In addition, system board sockets will be designated by manufacturers to support either SATA, PCIe, or in some cases, both. It is important to check your system’s manual to verify which technologies are supported; in some motherboards, there can even be sockets that support both and some limited to either SATA or PCIe only.
(taken from Kingston M.2 FAQ)
The XP941 and the SM951 are similar cards, make sure if you buy either you buy the AHCI version, seems the PCIe (NVMe) will not work, however some posts seem to have the XP941 installed which is a PCIe ssd as far as I know and some are actually saying that they only use PCIe x2 lanes instead of x4 which is strange as it shouldn't be working according the 9343 manual.
But you have to check you might actually get the 950 Pro to work if people got the PCIe version working.