I have a very powerful Mac Pro desktop that I would like to install Win 8.1 64bit onto to be able to use Win software for recording audio/video. It was using El Capitan OSX on the Mac and I tried using the BootCamp to install Win 7 and/or Win 8.1 64bit, but it acted as if it was installing then when restarting from installation, it simply will not boot past a black screen. I am not Mac savvy, so I do not know where to go from here. I felt like this would be a great project for someone out here who wanted to face the challenge or may already know how to handle this problem. Thank you for your help ahead of time.