Was running merrily along when I noticed phantom zombie sounds. Then all of the phantom sounds sort of merged together until they formed a horrifying loop. The game then froze (with the horrifying cacophony of phantom noises now merged into an unholy buzz) and I couldn't alt-tab (or ctrl-alt-del) out. Screen went blue, and I had to restart my PC. First BSOD in DayZ for me, though, so I guess I've been doing alright!! :)