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When I press Alt + Tab to switch between windows, the view messes up (not always, but very often). Sometimes it shows just noise where every pixel is another color, and sometimes it shows artifacts from other (closed) programs.

Here is a screenshot, the stuff in the upper half of the screen is from a game I had opened about an hour ago. I have two screens, this is the smaller one:

enter image description here

I think this problem started when I installed CompizConfig, I'm not sure.

• Ubuntu 12.04 LTS 64-bit
• Graphics Driver VESA: PARK
• ATI/AMD Radeon HD 5430

Does anyone else have this problem or know how to fix it?

share|improve this question
Do you have on-board display? You can try to switch the output to on-board display to check if it's the hardware problem of the display card. – Kenneth L Mar 24 '14 at 3:25
I don't, but it didn't seem to be a hardware problem since it only happened when opening the window-switcher. However I've now installed Cinnamon. – jomo Mar 24 '14 at 21:44

Open a terminal and execute these:

mkdir ~/tmpbak
mv -rt ~/tmpbak ~/{.compiz-1,.gconf} ~/.config/{compiz-1,dconf}

Log-out and back in, and you should get the problem fixed.

share|improve this answer
thanks for the answer, I cannot test this anymore because I have now installed Cinnamon. – jomo Mar 24 '14 at 21:42

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