Yea some times when i boot the system seems unable to fin the driver i just power of close the psu and draw the power out then open the psu and boot again then it can find the driver (this is not happening offten).
I got the sata on AHCI.
The 950 pro is the only m.2 driver and its the only one i am having on the expansion card the other driver is a 850 ssd 2,5 form factor (so i have only the one slot full on the card the ''M key'').
I will try using the sata connection. since i am not using the sata connection just the pci.