MSI Z170A Gaming M5 not recognizing SM951 as UEFI

[airwalkrr]

I've got a brand new build and I am running into an issue that keeps popping up. Here's the hardware:
CPU: Intel Core i5-6600K 3.5GHz Quad-Core Processor (Purchased For $229.99)
CPU Cooler: Noctua NH-D15 82.5 CFM CPU Cooler (Purchased For $93.04)
Motherboard: MSI Z170A GAMING M5 ATX LGA1151 Motherboard (Purchased For $189.99)
Memory: G.Skill Ripjaws V Series 16GB (2 x 8GB) DDR4-2800 Memory (Purchased For $129.99)
Storage: Samsung SM951 256GB M.2-2280 Solid State Drive (Purchased For $196.99)
Storage: Seagate Barracuda 2TB 3.5" 7200RPM Internal Hard Drive (Purchased For $70.98)
Video Card: EVGA GeForce GTX 980 Ti 6GB Superclocked+ ACX 2.0+ Video Card (Purchased For $678.95)
Case: Phanteks Enthoo Pro ATX Full Tower Case (Purchased For $99.99)
Power Supply: EVGA 850W 80+ Gold Certified Fully-Modular ATX Power Supply (Purchased For $99.99)
Optical Drive: LG WH16NS40 Blu-Ray/DVD/CD Writer (Purchased For $49.99)
Operating System: Microsoft Windows 10 Pro OEM (64-bit) (Purchased For $139.99)
External Storage: Samsung D3 Station 3TB External Hard Drive (Purchased For $94.99)

The main issue right now is that the M.2 drive (SM951) is not being recognized as UEFI all the time, and I have no idea why. In the BIOS when I first installed the SM951, it wasn't even being detected by the BIOS at all. This was eventually fixed by simply disconnecting and reconnecting the drive. After that, for a while the whole build was working mostly as expected. I was able to get Win10 installed with all components attached and everything was working except an MX100 from my previous build I intended to use as a backup (you can read about that issue here if you want). Shortly after updating the firmware for MX100, the M.2 drive went back to being unrecognized as UEFI and I was unable to boot Win10.

Currently, my BIOS will not recognize the M.2 drive in either M.2 slot as UEFI. If I switch off UEFI in the BIOS, it will not detect the drive at all. I'm somewhat at a loss for what to do now. Can anyone offer some advice?

 

[airwalkrr]

Here are a few things I have tried so far:
-Clear CMOS, no difference
-unhooked all hardware but the CPU, one stick of RAM, and the M.2 drive; won't boot, BIOS still does not recognize M.2 drive as UEFI
-hooked up optical drive and tried to repair win10; tried to do a reset and received error message "unable to reset your pc. a required drive partition is missing windows 10"
-tried to reinstall windows 10; M.2 drive appeared as a possible drive. I selected Format, then tried to install to the drive, but it when I try to select the drive, I receive the error "We couldn't create a new partition or locate an existing one. For more information, see the Setup log files." This might be because the drive isn't recognized as UEFI. I don't know.

Still searching around for answers.

 

[airwalkrr]

And FYI, the BIOS DOES detect my optical drive as UEFI, so that is not a problem.

 

[airwalkrr]

I just updated the BIOS from E7977IMS.100 (what it shipped with) to E7977IMS.120. Still no luck. The vast majority of the tutorials I am finding online for this M.2 drive are for X99 boards, often ASUS boards, and although they have offered a little insight, no specific help with my particular issue has been gleaned.

 

[airwalkrr]

For those who are experiencing a similar issue to mine, I finally found an answer at the MSI forums. I had to clean the drive using DISKPART. Here's a link to the post: https://forum-en.msi.com/index.php?topic=260437.0