Thanks for your report. I'm not a developer, just having a quick glance on your logs:
Your system log shows I/O errors on /dev/sdb, a 1.00 TB storage. This can be due to bad cabling / connectors or due to a bad disk. Additionally, the USB connection to the WD My Passport 25E1 drive was reset twice (this may be a follow-up issue). Your system log refers to several "Firmware Bug", "ACPI Warning" and "ACPI Error" events. Some of these refer to your graphics card / chipset. Firmware bugs can sometimes be worked around by Linux, but the better approach is a firmware upgrade. Your system currently runs BIOS 40CN28WW(V2.14) 10/07/2011 BIOS version 40CN33WW (released on 02 Sep 2012) is the latest version available: https://pcsupport.lenovo.com/de/en/products/LAPTOPS-AND-NETBOOKS/LENOVO-G-SERIES-LAPTOPS/LENOVO-G570-NOTEBOOK/downloads/DS018378 The X graphics server (which provides the foundation to make your graphical desktop work) seems to start up fine with radeon (AMD/ATI graphics) acceleration. Summing up, at this point, these seem to be hardware / firmware specific issues, not bugs in Ubuntu. Because of this, I will mark this bug as "incomplete". If you can solve these hardware / firmware issues and the system still fails to boot properly, please update this bug report and reset the status to "new" (or file a new bug). If you would like further support, both professional (commercial) and volunteer / community support are available: https://www.ubuntu.com/support https://www.ubuntu.com/support/community-support ** Changed in: xorg (Ubuntu) Status: New => Incomplete -- 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/1830616 Title: $ ubuntu-bug xorg To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1830616/+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