We have a number of reports of the gfxpayload=keep causing black screens on boot. It would be good to confirm that this issue is resolved with just that single change. You can set that via /etc/default/grub, adding GRUB_PAYLOAD_LINUX=text and then running sudo update-grub.
Also are you using the proprietry ATI drivers or open source? ** Tags added: kernel-key-gfxpayload -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/609428 Title: Unable to boot after upgrade -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
