Was running 3.8.17 and experienced this problem. Upgraded yesterday to 3.8.18, but still the same
On each reboot either only 2 of my 3 Displays are available, or when all 3 Displays are available, then my Onboard RJ45 Network device is not working, and I have to switch to Wireless
It is always the Display connected to my usb-c port which disappears - never my main laptop display or display connected to the onboard HDMI port.
As it is now, all 3 displays are working but my Onboard rj45 network interface cannot be brought up
I can imagine that the USB-c port gets brought up in a late stadium of the boot process and prolly will disconnect too when the machine goes into suspend/hibernate.
As for the network commands, I'd start using the "ip" command as "ifconfig" will soon be deprecated.
i.e "ip addr show" to see all the interfaces and to bring up the interface: "ip link set enp4s0 up"
Or try using "dhclient enp4s0"` to let dhcp set the IP addr once the interface is up.
Worryingly both network and USB-C interfaces rely on udev to be brought into action.
If everything worked before 3.8.17 it might be worthwhile to downgrade the kernel and see if that will keep everything running smoothly ....... or upgrade to the very latest.
As for debugging I'd check the syslog files as well dmesg for errors in relation to what's happening on startup.
