Pot. ("likely") bug #320562
Please attach the output of "qdbus org.kde.kwin /KWin supportInformation"

KWin Support Information:
The following information should be used when requesting support on e.g. http://forum.kde.org.
It provides information about the currently running instance, which options are used,
what OpenGL driver and which effects are running.
Please post the information provided underneath this introductory text to a paste bin service
like http://paste.kde.org instead of pasting into support threads.

==========================

Version
=======
KWin version: 4.10.5
KDE SC version (runtime): 4.10.5 "release 4"
KDE SC version (compile): 4.10.5 "release 4"
Qt Version: 4.8.5

Options
=======
focusPolicy: 0
nextFocusPrefersMouse: false
clickRaise: true
autoRaise: false
autoRaiseInterval: 0
delayFocusInterval: 0
shadeHover: false
shadeHoverInterval: 250
separateScreenFocus: false
activeMouseScreen: false
placement: 4
focusPolicyIsReasonable: true
borderSnapZone: 10
windowSnapZone: 10
centerSnapZone: 0
snapOnlyWhenOverlapping: false
showDesktopIsMinimizeAll: false
rollOverDesktops: true
focusStealingPreventionLevel: 1
legacyFullscreenSupport: false
operationTitlebarDblClick: 
commandActiveTitlebar1: 0
commandActiveTitlebar2: 30
commandActiveTitlebar3: 2
commandInactiveTitlebar1: 4
commandInactiveTitlebar2: 30
commandInactiveTitlebar3: 2
commandWindow1: 7
commandWindow2: 8
commandWindow3: 8
commandWindowWheel: 31
commandAll1: 10
commandAll2: 3
commandAll3: 14
keyCmdAllModKey: 16777251
showGeometryTip: false
condensedTitle: false
electricBorders: false
electricBorderDelay: 150
electricBorderCooldown: 350
electricBorderPushbackPixels: 1
electricBorderMaximize: true
electricBorderTiling: true
electricBorderCornerRatio: 0.25
borderlessMaximizedWindows: false
killPingTimeout: 5000
hideUtilityWindowsForInactive: true
inactiveTabsSkipTaskbar: false
autogroupSimilarWindows: false
autogroupInForeground: true
compositingMode: 1
useCompositing: true
compositingInitialized: true
hiddenPreviews: 1
unredirectFullscreen: false
glSmoothScale: 2
glVSync: true
colorCorrected: false
xrenderSmoothScale: false
maxFpsInterval: 17
refreshRate: 0
vBlankTime: 6144
glDirect: true
glStrictBinding: false
glStrictBindingFollowsDriver: true
glLegacy: false

Screens
=======
Multi-Head: no
Number of Screens: 1
Screen 0 Geometry: 0,0,1366x768

Compositing
===========
Qt Graphics System: raster
Compositing is active
Compositing Type: OpenGL
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Intel(R) Ivybridge Mobile 
OpenGL version string: 3.0 Mesa 9.0.2
Driver: Intel
GPU class: IvyBridge
OpenGL version: 3.0
Mesa version: 9.0.2
X server version: 1.13.2
Linux kernel version: 3.7.10
Direct rendering: yes
Requires strict binding: no
GLSL shaders:  yes
Texture NPOT support:  yes
Virtual Machine:  no
OpenGL 2 Shaders are used

Loaded Effects:
---------------
kwin4_effect_zoom
kwin4_effect_login
kwin4_effect_slidingpopups
kwin4_effect_minimizeanimation
kwin4_effect_translucency
kwin4_effect_screenshot
kwin4_effect_slide
kwin4_effect_desktopgrid
kwin4_effect_maximize
kwin4_effect_fade
kwin4_effect_dialogparent
kwin4_effect_highlightwindow
kwin4_effect_taskbarthumbnail
kwin4_effect_presentwindows
kwin4_effect_blur
kwin4_effect_logout
kwin4_effect_dashboard
kwin4_effect_outline
kwin4_effect_startupfeedback

Currently Active Effects:
-------------------------
kwin4_effect_blur

Effect Settings:
----------------
kwin4_effect_zoom:
zoomFactor: 1.2
mousePointer: 0
mouseTracking: 0
enableFocusTracking: false
followFocus: true
focusDelay: 350
moveFactor: 20
targetZoom: 1

kwin4_effect_login:
fadeToBlack: false

kwin4_effect_slidingpopups:
fadeInTime: 250
fadeOutTime: 250

kwin4_effect_minimizeanimation:

kwin4_effect_translucency:
decoration: 1
moveResize: 0.8
dialogs: 1
inactive: 1
comboboxPopups: 1
menus: 1
individualMenuConfig: false
dropDownMenus: 1
popupMenus: 1
tornOffMenus: 1

kwin4_effect_screenshot:

kwin4_effect_slide:

kwin4_effect_desktopgrid:
zoomDuration: 300
border: 10
desktopNameAlignment: 0
layoutMode: 0
customLayoutRows: 2
usePresentWindows: true

kwin4_effect_maximize:

kwin4_effect_fade:

kwin4_effect_dialogparent:
changeTime: 300

kwin4_effect_highlightwindow:

kwin4_effect_taskbarthumbnail:

kwin4_effect_presentwindows:
layoutMode: 0
showCaptions: true
showIcons: true
doNotCloseWindows: false
ignoreMinimized: false
accuracy: 20
fillGaps: true
fadeDuration: 150
showPanel: false
leftButtonWindow: 1
rightButtonWindow: 2
middleButtonWindow: 0
leftButtonDesktop: 2
middleButtonDesktop: 0
rightButtonDesktop: 0
dragToClose: false

kwin4_effect_blur:
blurRadius: 12
cacheTexture: true

kwin4_effect_logout:
useBlur: true

kwin4_effect_dashboard:
brightness: 0.5
saturation: 0.5
blur: false

kwin4_effect_outline:

kwin4_effect_startupfeedback:

thanks. assuming it's not some random memory corruption in the intel driver ;-)

*** This bug has been marked as a duplicate of bug 320562 ***