I'm having a similar problem using a DELL Inspiron 3646 with an Intel J2900 CPU.
I'm having good results with the following settings: ALREADY TRIED: Disable VT-d(Intel Virtualization Technologies) in the BIOS /etc/default/grub: GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_pstate=disable" then $ sudo update-grub and /etc/modprobe.d/i915.conf: options i915 semaphores=1 then $ sudo update-initramfs -u NOT TRIED: /etc/X11/xorg.conf.d/20-intel.conf Section "Device" Identifier "old intel stuff" Driver "intel" Option "Shadow" "True" Option "DRI" "false" EndSection /etc/X11/xorg.conf.d/20-intel.conf Section "Device" Identifier "Intel Graphics" Driver "intel" Option "NoAccel" "True" EndSection /usr/share/X11/xorg.conf.d/20-intel.conf: Code: Section "Device" Identifier "Intel Graphics" Driver "intel" Option "AccelMethod" "uxa" EndSection -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1454868 Title: Ubuntu 15.04 Freezes Totally To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1454868/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp