[mythtv-users] X11 freeze after screen blanking with Haswell mobile

[Matt Garman]

I just rebuilt my frontend-only machine using an Intel NUC D54250wyk.
This uses an i5-4250U CPU, with integrated HD graphics 5000.  My
understanding is that this is basically a laptop Haswell CPU/GPU.

I'm running CentOS 6.6 and MythTV 0.27.4 from scrpms.  Everything
works fine except that after the screen blanks due to inactivity,
about 65% of the time, the screen is completely frozen.

I'm not using any screensaver, just letting Xorg do the blanking.
When the screen is frozen, I can still move the mouse cursor around.
But I can't see anything else on the screen.  The workaround is to
explicitly kill the X server (Ctrl-Alt-Backspace), then re-launch
mythfrontend.

Another curious thing I've noticed: some of the time, when the screen
is frozen like this, it's not black, but frozen on a frame (i.e. still
image) from something we recently watched!  At first I thought it was
my kids playing with the remote, but we started keeping the remote out
of their reach, and it's still happening.

A final note: I usually start mythfrontend from a terminal.  Most
people have noticed, in X, the mouse pointer is a little arrow, but
when you mouse over a focused terminal window (xterm), then the mouse
pointer turns into a cursor (looks kind of like a capital "I").  When
the screen is in this frozen mode, and I hit "Alt-Tab" (to switch from
mythfrontend to xterm), and I mouse over to where I know the terminal
is, I see the cursor shape change.  So it's almost as if X is
functioning correctly, just not updating the display.  I also don't
see any errors in myth's log or in the Xorg log, so that also suggests
to me that the driver/hardware "thinks" everything is OK.

Anyone seen anything like this?  Any thoughts on how to fix it?

Thanks!