There are 2 kinds of UEFI  CSM and Secure boot.

Secure Boot ON = CSM OFF

Secure Boot OFF = CSM ON

CSM (Compatibility Support Module) is not enabled by default on the Boot screen in your BIOS.

Click on CSM to show further options.

Look for the option Launch Storage OpROM Policy within CSM. Change the default setting from Legacy Only to UEFI Only.

In the Storage Configuration screen the SATA mode is default set to AHCI, which can change to RAID or IDE. (DO NOT set IDE at any point.) Most often this will be left as AHCI, as you may be using additional SATA drivers or have one of the AHCI PCIe SSDs.

Save and Exit from the BIOS and then go back into it.

Thanks SpeedStep for your information.  All good and informative.

The latest bios for my Dell T5600 is version A14.

It's interesting that there is no mention of "Secure Boot" anywhere in the firmware.  I looked!

I WAS able to get past the UEFI/USB boot issue.  Ping me if someone else is interested in the details.

I was hoping that booting the windows installer in UEFI might solve the problem, but no.

So I think I'm back to needing a BIOS update that recognizes PCIe device as a bootable device.

If I could flash the firmware myself I'm sure it would work.

http://www.win-raid.com/t871f16-Guide-How-to-get-full-NVMe-support-for-Intel-Chipset-systems-from-Series-up.html

So as before...  Any ideas or suggestions appreciated.

Thanks! 

Secure boot is under SECURITY IN BIOS.

NVME F6 DRIVERS ARE NOT OPTIONAL

https://downloadcenter.intel.com/download/23929/Intel-SSD-Data-Center-Family-for-NVMe-Drivers

Thanks SpeedStep  I'm with you, but I have to assume this firmware is different and doesn't incorporate the secure boot settings, or what ever is needed to detect a PCIe boot device.  Here is what I see under Security settings, and the boot options screen.

Thanks for the link to drivers.  I had injected those into the windows install image, otherwise the install doesn't see the drive at all.  But you saw the results.  I can see the drive, and I can even install windows on to the drive, but I can't boot it, as the windows installer error message points out in the prior post.

I keep coming to the conclusion that there is some firmware update I need that will do the trick.

Any help or or information appreciated. 

There is a place in the bios to ADD a boot option where it says Boot Sequence.  UEFI is only booting USB right now.  The NVME drive should show up as NVME or AHCI boot in the pci bus.  I don't have your system so I cant say how or IF it would work.  When it does adding the boot option looks like this. You MUST be using Windows 7 SP1 or Higher.  I can tell from your install screens you are trying to install WINDOWS 7 with NVME.  You cant add SP1 later.  There is also a required HOTFIX pre install.

https://support.microsoft.com/en-us/kb/2990941

FS0: Alias(s):HD21a0e0b:;BLK1:
      PciRoot(0x0)/Pci(0x1D,0x0)/USB(0x0,0x0)/USB(0x4,0x0)/HD(1,MBR,0x0003B)
  FS1: Alias(s):HD23a0a1:;BLK4:
      PciRoot(0x0)/Pci(0x1F,0x2)/Sata(0x0,0x0,0x0)/HD(1,MBR,0x00000000,0x3F)

 A "B Keyed" drive is NOT NVME and your bios may not be NVME compatible.  My XPS 8900 has this but its a windows 10 bios machine.

I am in exactly the same situation described by kmzeitz, trying to install Win10 on a Intel 750 PCIe SSD in a T5600 with the A14 BIOS. The installation from a UEFI USB works, the SSD is in the PCIe x16 slot and visible as 'mass storage' in the PCI information. The 'Windows Boot Manager' option is created as a UEFI boot option but I cannot boot from it.

The latest bios for my Dell T5600 is version A14. It's interesting that there is no mention of "Secure Boot" anywhere in the firmware.  I looked!

That system is an early UEFI system. It likely has a SMBIOS of 2.6 and hence no Secure Boot (even with the latest BIOS update). Dell systems with an SMBIOS of 2.8 and the latest BIOS version have Secure Boot. More details here:

http://dellwindowsreinstallationguide.com/uefi/ 

Hi Philip - I have a Precision T3610.  Is NVMe boot supported?  I have the latest BIOS from Dell, it shows up as SMBIOS 2.7, also I have UEFI boot and Secure Boot turned on.  I can successfully boot to my USB installation drive, and I can install Windows 10 onto my PCI-Express NVMe drive.  However, after install, it just won't boot from that NVMe drive.

It would be really helpful if Dell would just come out with a list stating PCI-Express NVMe boot support and which models do or don't support it.

Prior to purchasing my new hard drive, I did an online chat with Dell Support and asked them if I could boot to PCI-e NVMe on my T3610.  He flat out said "yes, it's supported".  I have a chat log e-mail to prove it.  So I bought my drive and tried to get it to work, only to find out that it's not working :(

It's an Intel 600p NVMe drive.

I have no problem installing Windows 10 (latest build 1607) to the NVMe drive.  The Windows 10 installation process see the drive just fine without loading any extra drivers.

The problem comes when I try to boot the T3610 from the NVMe PCI-E drive, it just won't do it.

I feel like the BIOS is just missing a switch that says "enable NVM boot from PCI-e drives" and that would resolve my issue.  A quick BIOS update to enable that and I assume it would work after that.  (wishful thinking, I know)

What model of drive did you purchase? I would imagine Windows 10 RS1 should have the preinstallation SATA drivers required inbuilt but can have a look if I have some more details.