Nvidia 331.20 driver = black screen

I’m having issues with 331.20 with my gtx680 in ubuntu 13.10. If I logout and login a couple of times I eventually get a black screen with vga signal lost. This is reproducable. I have the same issues running StemOS. If if swith between bigpicture and desktop mode, I eventually get a black screen. So it’s clearly a driver issue. Default 319.xx ubuntu driver works fine without these issues.
nvidia-bug-report.log.gz (345 KB)