Running Windows 7 64 bit, gfx AMD 280x on latest drivers, though I had the same issues on older drivers I was using before I updated specifically to try and resolve this issue.
I don’t know a definitive way to reproduce the issue, but it happens a lot, several times per dungeon run. I want to say it happens more frequently when I spam the hotkey I have bound to escape/close menu/etc (X), but that could be anecdotal.
To clarify since I’ve seen this posted as a solution (or at least temporary resolution) for similar sounding issues elsewhere, running in DX9 safe mode with Bloom/DoF off doesn’t actually seem to help stop the issue from happening, or even lessen how often it occurs. It does seem to cause another issue that is also very annoying though which is that water stops rendering which also created issues in certain areas/dungeons. The only solution to the Black Screen is to fully close the game and relaunch it via alt+f4 or Task Manager, I managed to figure out how to navigate to the main menu from the black screen and was able to continue but when I loaded back in it was still a black screen unti I relaunched the game.
Hopefully you can figure out what the cause is because while normally an annoyance that simply has me relaunch the game the last time this happened was after the first time I killed the Deadwatch boss and thus I missed all the dialogue and lore as well as a few items I left behind and am probably going to set the game aside until a fix comes along. Thanks.