Yep, just hit the same problem. It looks like the kernel doesn't have that module configured. I solved the problem by removing xserver-xorg-video-mach64 and xserver-xorg-video-ati (and xserver-xorg-video-all) and it seems to work on whatever it's fallen back on.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1375511 Title: XServer modprobe: FATAL: Module mach64 not found. 14.04.1. 12.04 worked great To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-mach64/+bug/1375511/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs