try downloading the Intel® Rapid Storage Technology Driver f6flpy-x64.zip from here [URL] unzip the file and put the folder on the root of your win 10 usb media. when the install asks for drivers point to the floppy folder you put on the usb drive I suggest to you that your pc has a win 10 home key embedded in bios so your resulting install may well turn out to be the home edition. best way I've found for the upgrade is to put the retail pro key in settings>update and security>activation>change product key.  
I recieved 2 new XPS 8940 towers which came with Windows 10 Home edition, I tried upgrading from Home to Pro with a license key I got but it kept failing, I'm trying to install the Windows 10 Pro using an old ISO I have but when I get into the Windows Setup screen I can't find a a drive.    Anyone know how to install windows 10 on the new XPS 8940 or know where to find the drivers?
XPS 8940 Windows 10 Pro Installation