So the DVD works fine installing on a VM or on another machine, so it isn't that. It's also a disk that was burnt today, and is the 1607 build, downloaded today.
Incidentally my other machine also can't boot from it, but I think that's because the BIOS doesn't seem to support booting from PCIe. It's a 2011 PC built for FreeNAS with the latest 2013 BIOS, and there aren't any updates coming any time soon.
Since I've not really given my reasoning for this, I'll do my best to explain what I'd like to do;
I'm planning on booting from the SM951. I have 2x Intel 335 240Gb SSDs which I'd like to stripe under Storage Spaces, and 4 2Tb disks I'm thinking of migrating from ZFS to Storage Spaces (Parity) and also to try out ReFS.
One of my 335s is currently running Windows 10 just fine, but it only boots when connected to an ODD port or Bay 1.
Since other people have managed to get it working I thought I'd give it a go, but every time I've tried moving Windows boot to a PCIe slot I always ran into issues. :/
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So I tried installing it on my other PC, then transferring it across. Didn't work, some issue with BSD.
Tried collating the drivers (.sys and .inf) on a USB drive for the installer to use, looked hopeful but rejected them. Maddening that I can actually see the drive and manipulate it using diskpart, but not with the Windows installer.
[doublepost=1473549457][/doublepost]Ok, so for the first time ever, I think I've managed to get it working. Installation appears to be the weak point, not actually using it.
The BSD issue I ran into earlier looks like after a reboot the install media is still required for something. I didn't have the disk in the Mac after re-installing the SM951, so the install broke.
So I guess my advice would be if you have a secondary system you don't mind ripping apart to initially install Windows on this is ideal. Run the install on a regular PC first, but rather than reboot, shut down. Take the SM951 and Windows 10 media out, install the SM951 in the Mac Pro and start, holding Alt. At the boot screen load the Windows 10 disk, but boot from the EFI Boot partition on the SM951, and the install should continue