Yes this is a fresh install of Win 10 Pro x64.  My boot disk partition table is set to MBR.  Storage media is a samsung 850 Pro 512 GB hooked up to SATA_3_0.  Not using M.2 storage anywhere, everything is connected up to SATA.  I have a total of 6 drives currently attached to the SATA_3_x where (x|0-5).  No drives connected to the 2 ASMedia SATA ports, although I have cables inserted there they're not attached to any drives (makes it easier to add storage in the future).  Also, I should list out my peripheral cards:

PCIe1 (x1) = empty

PCIe2 (x16) = EVGA GTX 970 SC

PCIe3 (x1) = SATA3 PCIe expansion card with 4 ports: 2x connected to 2 different optical drives, 2x connected to 2 HDDs

PCIe4 (x8) = USB3 expansion card

PCIe5 (x1) = empty

PCIe6 (x4) = Sound Blaster audio card

I would try unplugging these and see if that fixes things, but the problem itself is hard to reproduce.  If I find a reproducible way I might try this, if there are no other suggestions.

EDIT: Is it possible the motherboard's UEFI doesn't like MBR partition table?

Ok I have another interesting data point to add.  Tonight I tried installing one program (Partition Master) and I tried testing out a feature (create a Windows Preinstallation Environment Disk) that got hung (it never went anywhere, no window popped up).  So I exited the program and had to kill the application manually in Task Manager.  I went to shut down my computer, and it took about 3-4 minutes before it finally shut down.  Windows would appear to log off in a few seconds, the screen goes black, and the computer remains on for 3-4 minutes.  Thinking for sure the UEFI would reset, I took a video of me turning on the computer, but somehow it didn't reset.  When it logged me on (I have no password set) I could not move my mouse.  I unplugged and plugged it back into the same USB 2 black plate that connects directly into the motherboard's USB2 slots and it works fine.

I've had this problem earlier but I thought it went away.  Is this possibly related?  Or something else??  Maybe the UEFI update I did to 3.10 was faulty?

Updates:

[I'm using these posts for notes]

I rebooted it again right after the last power cycle, and this time my USB mouse (connected to the USB2 backplate, which connects directly into the motherboard's USB2 pins) didn't work even after unplugging and plugging it back in.  I then tried plugging it into a slot in the USB 3 PCIe adapter.  This caused Windows to crash giving me the DPC_WATCHDOG_VIOLATION error.  I looked into this and I have the iaStorAC.sys driver, and not the iaStor.sys driver some people seem to have issues with (for the SATA AHCI controller).  The driver is dated 5/23/2018 so quite recent.  I start the PC back up again and right after login Windows (re-?)installed the driver for the USB3 PCIe card, the manufacturer being "Renesas".  It's looking like this USB3 hub/card caused the unexpected shutdown.

I found some *.dmp files in the directory %windir%\LiveKernelReports\USB3HUB, and using Blue Screen Viewer (program) I didn't find anything that stood out to me.

Finally, I looked in the Windows Event Viewer to see what sorts of errors are occurring.  A couple of interesting ones popped out at me.  The "source" for each failure event are listed on a single line, followed by the description, and any of my own commentary, in chronological order:

8/13: 14x of NTFS ("A corruption was discovered in the filesystem Windows 7").  I have an image of my previous Win 7 installation I'm using to transfer some stuff over, and it's connected via the front USB3 panel.  This drive is sometimes connected when I shut down the computer, I don't know if this correlates with any of my issues yet.

8/14: Kernel-Boot ("Windows failed startup with error status 0xC00000D4"), Kernel-Power ("The system has rebooted without cleanly shutting down first.  This error could be caused if the system stopped responding, crashed, or lost power unexpectedly"), EventLog ("The previous system shutdown at [such and such time] was unexpected").  These happen a lot in fact, and all 3 are in the same order.

I should mention that up until a few days ago I had an IDE drive connected to one of the SATA ports (ASMedia chipset), using an IDE --> SATA adapter.  I discovered that once I pulled that out of my system it solved a whole bunch of issues, I didn't lose my mouse on Windows startup, and I was getting less of the UEFI failing to boot issue.  And it solved another minoir problem I haven't mentioned yet, that being every time I plug a USB3 device into a USB3 port (any port going to the motherboard) Win 10 would tell me to plug it into a USB 3 port so it'd transfer faster.  That adapter caused a lot of corruption for that drive (I had a backup so it's fine).  In fact I think that adapter may be the cause of all or nearly all of the issues, and I'm dealing with the residuals of it now.

Also unfortunately I could not find any memory dump files, even though Windows Event Viewer claimed it did.

I don't even know if these two events are related.  Does Windows fast boot save drivers in its prefetch?  This may be causing the USB issue, but I'm not sure if that'd cause an issue with booting since that's not a Windows-specific problem.  I just tried deleting as much as I could from %windir%\Prefetch.

Help!!!  :(

I figured I should post here on how I resolved my problem, for anyone else who might be experiencing something similar.

Basically I replaced the motherboard with another one and everything has been working fine, even after many many restarts while overclocking my CPU.