I tried muhfi-asbin's solution (thanks for that!). After booting into recovery mode, I installed "fglrx-updates" and rebooted. So far, my computer seems to be fine.
Martin CPU: AMD A4-4000 Mainboard: MSI MS-7721 Memory: 2GiB DDR3-1333 Graphics card: ATI Radeon HD 7480D -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1309578 Title: Ubuntu 14.04 suddenly reboots when booting from Live USB AMD A8 6600k To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1309578/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
