On the PC with the problem the issue occurs whether I run the game fullscreen, fullscreen (windowed), or windowed. Over the course of those months, I have on occasion used a different computer, but with the same monitor and dvi cable, at the same resolution and refresh rate (2560x1440) and everything works fine, so I don't think the problem lies there. This problem will continue for a minute or two and then stop, it sometimes does not reoccur for days or weeks or maybe just a few hours, and then comes back for a few minutes or occurs near constantly. there is no cursor or anything) for a second or two at a time.
So, for several months now I have had this issue where while playing the game on a PC I upgraded to Windows 8.1, the screen will start flashing black (the whole screen, i.e.
