From the /var/log/Xorg.0.log.old, it looks like DRM failed to become master. I'm experiencing a similar problem where a software rasterizer kicks in (making everything very slow) at bug 446641.
From the /var/log/ Xorg.0. log.old, it looks like DRM failed to become master. I'm experiencing a similar problem where a software rasterizer kicks in (making everything very slow) at bug 446641.