First try installing windows again, with either resetting the BIOS / UEFI or not. 

But this time DELETE the partitions you see.  DON'T use format. 

If this does not work, try going to Samsung and DL the magician and read about running in DOS as a boot. If this won't work with your 850, I'll try to find a generic erase. 

Never use any HDD wipe or zero tool.  

This is from Samsung -  DOS : 

Most all SSD MFG's have a tool for secure erasing,  you run it in DOS. You make a bootable DVD or USB flash drive. 

What brand and model is it, let me see what they have if any. 

Clear CMOS for your board and go into BIOS / UEFI, reset storage to RAID, go to BOOT page and make sure ROM is enabled, and any IGPU or GPU settings. 

If you want, go back and try windows install, but this time DELETE the partitions, all of them, then you should see the one unallowcated, hit NEW and try it.

I can't get into the op-ROM.  I've tried every combo of Cntrl-i, m, or g with RAID/AHCI.  I've been creating the array with the Intel RST utility that appears under the Advanced tab in the UEFI after setting the storage mode to RAID.

At the top you should see - Intel Rapid Storage Technology- Option ROM - 13.1.0.2134

Were you talking about when the MOBO boots and you see the RST screen or were you talking about in the BIOS / UEFI .

I think because you didn't secure erase the drives, the partition was left. 

Remember, if you are installing UEFI, you will see unallowcated space and when you hit NEW, you will see 4 partitions, and you will install to primary. 

**** Only secure erase the drives, there's no need to format using windows, no reason to format from NTFS to NTFS.  

Windows will make GPT on the NTFS.

I just wondered about the driver because it specifically said RAID driver at the top of the iRST utility but I will take your more knowledgeable word on it.

I will erase (format?) the SSDs.  I didn't realize I should be seeing unallocated space but it makes sense.

Thanks for the help.

Which OS are you using ?

Just telling you, Just in case you didn't erase them.

You actually should see unallocated space and not a partition,  when you see unallocated space this is when you see the NEW option to make a partition. 

I think secure erasing the drives will work and then you'll see unallowcated space and then you can hit new to make the partition.

Are you trying to install in MBR or UEFI ? 

I'm not sure what you mean by loading windows  and driver onto USB,  but if you were able to boot from it, it should be ok.  

Better to install windows in UEFI. 

Just some info about your post on the option ROM. 

The option ROM you see is not a driver, that is the version of the Option ROM, 13.1.0.2134 is the version of the ROM. 

The RAID driver is the 13.1.0.1058. 

First, the machine components:

  Asrock x99 Extreme4 mobo

  Intel i7-5820 cpu

  EGVA GTX970 graphics card

  32 GB J Skill Ripjaws DDR4 2666

  2 x Samsung EVO 850 250GB SSD  

  WD Black 3 TB HDD

  EVGA SuperNOVA 850G2 80Plus Gold

The system was working fine when I experienced a power loss which corrupted the RAID0 array.

The system was not recoverable so I loaded the Windows ISO and drivers to a USB for re-installation.  I deleted the existing RAID0 volume and recreated it using the iRST utility.

Upon booting from the USB drive Windows see's the single RAID drive (composed of the two SSDs).  However, when I attempt to execute the "New" function to create the Windows partition I get a message that Windows cannot install on the RAID0 drive, partition 1.  The details say to make sure the drive is defined to the SATA  controller and compatible with this hardware.