Solved and thanks to Billy Tallis. A few quirks though, When I disabled CSM in the BIOS I lost my GTX 1060 VGA card and got three rapid beeps during boot and couldn't access the BIOS control panel. Changed to 'Auto' for CSM and both card and Optane 900P recognized. I wiped the 900p clean using Windows command shell 'Diskpart' and Windows began to install with no partition or BIOS warnings. However, it kept quitting somewhere around 30% saying it couldn't find required files even though I loaded the 900P drivers at the 'Load Drivers' screen. The VGA card was removed at this point, all SATA (except 860 EVO) and USB devices were disconnected. Finally cloned my existing 860 EVO Windows installation to the 900P using AOEMI, removed the 860, and everything is fine now. Again, thanks for all the input and help.