By Gigabyte system board uses "Intel Rapid Storage Technology. Version (c) 2003-11 Option-ROM" as a firmware function. This version does not support Win 10. I contacted Gigabyte and they pointed me to version 14 software drivers which do support Win 10. The only instructions that came with the drivers where to put it on a flash drive for Windows to read during the install process.

So I did this, but Win 10 crashed with a:
0xC1900101 - 0X40017failed in the second boot phase with an error during Boot operation.

Based on the three error messages that were given during the failed upgrade attempt, it does seem to be a disk read problem.

My best guess is that the upgrade did not see the drivers. Or maybe software drivers do not trump the firmware drivers. Anyone have any suggestions?