Thank you for your answer. As it happens, the bug stopped some time after I reloaded the grub files a few weeks ago. Since then a number of patches have been edited which may have also corrected the problem. I really don't know what happened but now I can enjoy Ubuntu without fearing a crash.
I had no temperature problems. you can close the case. Thank you again -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1737210 Title: sytem restart spontaneously To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1737210/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
