I had a strange problem with x on my laptop. I was able to boot into the command line, and log on as user or root. But when I started x the xserver started up, I got the x curser and then a small white square in the middle of a black screen and the whole system was locked. I had to shut it down with the power button. It continued to happen, no matter what window manager I put in ~/.xinitrc. Then suddenly, this morning, everything is fine. The system boots up as normal.
I'm not sure what I'm asking for. Has anyone come across anything similar?
I've not encountered this behavior. I'd start by reviewing the Xorg.0.log.