Also running 14.04, this has been a problem running on Ubuntu for some time, depending on the hardware. It's linked to the display of labels, so turning them off fixes things, though As far as I know, there are some workarounds out there, but no fix yet. See the previous threads: https:[log in to unmask] https:[log in to unmask] Oliver's workaround has been good enough for me so far, but it's treating the symptom, rather than the root cause. I still have to manually remove labels fairly often. Shane Caldwell McGill University On Wed, Sep 16, 2015 at 3:40 AM, Priyadarshan K <[log in to unmask]> wrote: > Dear Paul and Marcin > > Thank you for the suggestions. I am sorry I did not mention the specs. The > OS is Ubuntu 14.04 and the graphics card is nVIDIA GEFORCE 610M. > > I am not sure but I feel graphics support is fine because other > applications work fine including COOT except when centering on ligands. > > Thank you once again. > > Best Regards > Priyan >