Bug 772519

Description of problem:
The laptop display occasionally gets corrupt and frozen after turning back on after being in powersave state. The system continues to function normally in other respects.

Version-Release number of selected component (if applicable):
xorg-x11-drv-intel-2.17.0-4.fc15.x86_64
kernel-2.6.40.6-0.fc15.x86_64
gnome-screensaver-3.0.1-1.fc15.x86_64

How reproducible:
Intermittent. Happens every 2-3 days.

Steps to Reproduce:
1. Lock screen or wait for screen saver to kick in.
2. Wait for laptop screen to go into power save mode (i.e. it turns off)
3. Wake by moving the mouse or typing.
  
Actual results:
Vertical white/grey bars appear on one side of the laptop screen and gradually (within a second) spread to the other side.
The external monitor remains blank.
The system itself continues to function normally in all other respects.

Expected results:
Screen turns on again, and prompted for password to unlock screen saver.

Additional info:

I have an external monitor connected via the VGA port.

I can recover from this problem by doing:
1. Type in the password blindly (to unlock the screensaver).
   This results in the external monitor showing its part of the desktop.
2. Open a terminal.
3. Use 'xrandr' to list the displays.
4. Turn off the laptop screen output via xrandr:
   'xrandr --output LVDS1 --off'
5. Turn on the laptop screen output via xrandr:
   'xrandr --output LVDS1 --auto'
(At this point the laptop screen is now operational, but the displays are now mirrored.)
6. Go to 'System Settings -> Displays' and uncheck 'Mirror displays' and click 'Apply'.
(At this point things are usually back to normal, but sometimes the primary display has switched to the external monitor.)

Laptop details:
Dell Latitude E6520
Intel® Core™ i7-2720QM CPU @ 2.20GHz × 8 
Intel® Sandybridge Mobile

$  lsmod |egrep 'nou|i915'
i915                  378744  2 
nouveau               545674  0 
ttm                    55273  1 nouveau
drm_kms_helper         26474  2 i915,nouveau
drm                   193955  5 i915,nouveau,ttm,drm_kms_helper
i2c_algo_bit            5006  2 i915,nouveau
i2c_core               25712  7 videodev,i2c_i801,i915,nouveau,drm_kms_helper,drm,i2c_algo_bit
mxm_wmi                 1727  1 nouveau
video                  12340  2 i915,nouveau


$ lspci -v |grep VGA
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller])
01:00.0 VGA compatible controller: nVidia Corporation GF108 [Quadro NVS 4200M] (rev a1) (prog-if 00 [VGA controller])