many thanks for your help. I have done memtests two times before I posted this issue. There were no defects detected. What did you mean with '..if you have VTd enabled'?
I will now trying the following boot option: GRUB_CMDLINE_LINUX="i8042.noloop intel_iommu=off" it can take some days until I will post the results. mostly the freeze now occurs only when I use the external monitor in my office. Working with internal laptop display only the system seems to be quite stable. But I had also one freeze some days ago with in this situation. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1137817 Title: [ivb] System freeze after high memory usage To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1137817/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs