I agree with Kai-Heng. 17.04 is getting old and given all the good work that went into the 17.10 release, I recommend you switch to it Hagen. BTW, in 17.10, there is a problem on the XPS 15 (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1718936) booting from live CD and general use. You need nouveau.modeset=0 to the kernel boot options. On Sat, Oct 14, 2017 at 3:15 AM, Kai-Heng Feng