Those of us who are old enough will remember that before BSOD meant "blue screen of death" it meant "black screen of death", which was a black screen with a cursor.
Of course this was in character mode, and the cursor was a flashing underline cursor not a mouse cursor, and the cause appeared to be that the Windows for Workgroups 3.11 protocols didn't like sharing a wire with Novell Netware.
It seems unlikely that this is what you're seeing, unless you're in some sort of time warp, so it sounds like you've discovered a brand new "black screen of death" for the new century! Congratulations!