How many SSDs/HDDs do you have connected to your system?
I have the 950 in the M.2 slot and a 1TB SSD in the SATA 1 slot. the M.2 Drive is the only bootable drive so when it isn't recognized the startup hangs on "Please connect bootable device"
Please look inside the Boot tab and make sure the 950 is the first entry in the boot list. Also disable booting from other devices.
The problem is that the 950 isn't recognized at all (not just as a bootable drive), so it's not in the boot list at all when this issue comes up. It doesn't show up anywhere in the BIOS unless I completely cut power for a minute, then start the machine up again.