Dear Collegues, as I'm not alone with this issue, I would like to add at least a workaround. In principle this problem should occur with the graphic unit of any sandy-bridge and Ivy-bridge chip (thanks for the information from James Whittle) and newer versions of the mesa libraries. Although I do not know if the very latest version of the mesa libraries solve this issue.
After posting this issue to the mailing list, I have had contact to Paul Emsley and Edwin Pozharski and we found that the problem is somewhere in the mesa (openGL) libraries. I do not know enough of this to exactly localize the problem. Ubuntu utilizes mesa version 7.11, whereas Ubuntu 12.04 uses mesa version 8.0.2. The workaround is to selectively downgrade the mesa libraries (not beautiful, but functional). For ubuntu this can be done like this: Create a file called /etc/apt/preferences.d/mesa_711-pin-1050 (any other name will work). You need root privileges to do this. The content of the file should include all the mesa libraries including dependencies and look like this: #### File content starts below this line #### Package: libegl1-mesa libegl1-mesa-dbg libegl1-mesa-dev libegl1-mesa-drivers libegl1-mesa-drivers-dbg libgbm-dev libgbm1 libgbm1-dbg libgl1-mesa-dev libgl1-mesa-dri libgl1-mesa-dri-dbg libgl1-mesa-dri-experimental libgl1-mesa-dri-experimental-dbg libgl1-mesa-glx libgl1-mesa-glx-dbg libgl1-mesa-swx11 libgl1-mesa-swx11-dbg libgl1-mesa-swx11-dev libglapi-mesa libglapi-mesa-dbg libgles1-mesa libgles1-mesa-dbg libgles1-mesa-dev libgles2-mesa libgles2-mesa-dbg libgles2-mesa-dev libglu1-mesa libglu1-mesa-dev libopenvg1-mesa libopenvg1-mesa-dbg libopenvg1-mesa-dev libosmesa6 libosmesa6-dev mesa-common-dev Pin: release a=oneiric Pin-Priority: 1050 #### File content ends above this line #### Than simple update or better downgrade using apt-get: sudo apt-get update && sudo apt-get dist-upgrade That's how I got coot performance back on my X220. I hope this will help some ubuntu users with the intel notebooks. Cheers, Georg
