If you use Ubuntu Desktop 16.10 you will run sometimes into freezes of the Desktop with a Default Setup. Background: Theres a known Bug of the Deja-Dup Backup Service which is started by Cron. The Service take 100% Ram and 100% CPU usage. This did my PC with 16GB Ram too! Only HARD RESET helps to get back Control! Solution: Purge the deja-dup service with: $sudo apt purge deja-dup Use instead the „rsync“ tool by command line with users crontab to Backup your User Homes to external or 2nd. Disk. This should fix the problem.