Same problem on my ASUS GL703VD.
I tried the 18.04 beta today starting a live session with the suggested boot option (modprobe.blacklist=nouveau).
I can work using an external monitor connected to the HDMI interface. The laptop display become black during the boot just after few seconds but I can see the boot progress on the external monitor.
The system works fine with Ubuntu 17.10 with the old kernel 4.13.0-38-generic.
I tried the new kernel 4.16 with ubuntu 17.10 from the mainline repository but the problem is the same: black laptop screen during boot, external HDMI monitor working.
Same problem on my ASUS GL703VD. blacklist= nouveau) .
I tried the 18.04 beta today starting a live session with the suggested boot option (modprobe.
I can work using an external monitor connected to the HDMI interface. The laptop display become black during the boot just after few seconds but I can see the boot progress on the external monitor.
The system works fine with Ubuntu 17.10 with the old kernel 4.13.0-38-generic.
I tried the new kernel 4.16 with ubuntu 17.10 from the mainline repository but the problem is the same: black laptop screen during boot, external HDMI monitor working.