Thank you for your fast reply. Yes indeed, cryptsetup is installed. I installed a full disk encrypted system via the alternate installer. I'm sorry that I forget to mentition this in the first place. I attached the xrandr output, but I think it's not that usefull.
After setting GRUB_GFXMODE=1024x768 I see plymouth and after entering the cryptsetup/luks passphrase the system boots into X. ** Attachment added: "xrandr.out" https://bugs.launchpad.net/ubuntu/+source/plymouth/+bug/877278/+attachment/2559841/+files/xrandr.out ** Changed in: plymouth (Ubuntu) Status: Incomplete => New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/877278 Title: Boot fails on T61, screen stays blank To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/plymouth/+bug/877278/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
