I installed Steam to try some games on Linux, however I encountered afterwards a weird issue.
After boot, my ethernet connection began to disconnect from the internet after 30min-1hour. The wireless connection was not affected.
I managed to solve the issue by uninstalling Steam and reinstalling the network-manager by using the steps from here How to reinstall network manager without internet access? - Ask Ubuntu
1. First boot from a Ubuntu Live disk. 2. Once you go there open a terminal and run the below command, sudo apt-get download network-manager* This will download all the network-manager packages to the home directory. Now copy all the .deb packages to a folder in that pen drive or other partitions in your HDD and then reboot to your system. 3. Once you go there open terminal and do the following: cd /path/to/the/directory/where/.deb/files/are/located sudo dpkg -i *.deb The above command will install all the .deb files. 4. Now restart your network-manager by running sudo service network-manager restart. Now you have the package network-manager-gnome running again.
I don't really need Steam but wanted to share the solution for people that may encountered a similar issue.