I'm running 13.04, and have an Intel HD 5200 display, using the Intel drivers.
When the screen times-out and locks, most of the time one of two things happens:
- Either the current windows are still visible but frozen
- The screen is black and frozen
In either case the mouse pointer is movable, but I do not get the dialog for typing my password to unlock the screen.
But, if I switch to a VT and back (e.g. by pressing Ctrl + Alt + F2 then Ctrl + Alt + F7) the login dialog appears immediately.
I've searched all over the net for a few days and cannot find a remedy, though I can occasionally find someone else complaining of basically the same issue, such as here:
12.04 - Screen glitches / freezes after "Lock Screen"
Though I've a different version of Ubuntu, and a different Intel video chip.
The work-around to (of switching to VT and back) would be livable if it weren't for the fact that the contents of my screen are visible when it is locked up this way!
Any solutions out there?