Created attachment 34210 [details] glxinfo Distro: gentoo amd64 xorg-server: 1.7.6 xf86-video-intel: 2.10.902 (2.11 RC2) libdrm: 2.4.19 kernel: linux-2.6.33.1 mesa: 7.8_rc1 I upgraded xorg-server from 1.7.5, xf86-video-intel from 2.10-r1, mesa from 7.7-r1, kernel from 2.6.33-git6. Maybe also libdrm wasn't at version 2.4.19 before (I don't remember it, sorry). Before this upgrade kde desktop effects worked very well. I attached glxinfo. For further logs please see bugs #27168 and #27169.
It seems to be a mesa 7.8_rc1 bug. I'm closing the bug report.
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