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SDB Talk:Realtek 8169 driver problem
I have an Acer Predator Helios 300 laptop and run into this problem without dual-booting any other OS (just oS TW). If I start openSUSE from a cold boot, Ethernet works fine. If I reboot, Ethernet is broken. Upon adding reboot=efi to my kernel options, my laptop does a hard reboot (shuts off the power, keyboard light, and fans for about 2 seconds and then powers back on), and this allows Ethernet to return after reboots no problem.
Intestingly enough however, I don't notice this occuring on other Linux distributions; notably Fedora Workstation 27, Xubuntu 17.10, and Clear Linux.