Changing runlevels at boot time

[Alex]

Hi,
I have a fedora27 system that boots to a blank screen with the latest
kernels. This has been happening since the system was at least a
fedora26 system.

If I boot to multi-user first, then switch to graphical boot, it works fine.

Adding "3" to the grub command-line ("e" then append "3" to
linux16
line, then ctrl-x to boot) does not work to boot the system to
multi-user as per the documentation. However, adding
"systemd.unit=multi-user.target" does.

Also, the rescue kernel also works, but lacks networking. What's the
difference between these two kernels or these two grub invocations?
Notice I've also disabled selinux for now.

Any ideas why the system would become unresponsive and boot to a blank
screen with the latest kernels?

menuentry 'Fedora (4.13.13-300.fc27.x86_64) 27 (Workstation Edition)'
--class fedora --class gnu-linux --class gnu --class os --unrestricted
$menuentry_id_option
'gnulinux-4.13.13-300.fc27.x86_64-advanced-dedb2196-1933-4fa3-b8bd-5123930308b9'
{
        load_video
        set gfxpayload=keep
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='hd0,msdos1'
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root
--hint-bios=hd3,msdos1 --hint-efi=hd3,msdos1
--hint-baremetal=ahci3,msdos1 --hint='hd0,msdos1'
9522bf8d-db18-48e9-a7d9-ae9c52d4343d
        else
          search --no-floppy --fs-uuid --set=root
9522bf8d-db18-48e9-a7d9-ae9c52d4343d
        fi
        linux16 /vmlinuz-4.13.13-300.fc27.x86_64
root=UUID=dedb2196-1933-4fa3-b8bd-5123930308b9 ro security=0
        initrd16 /initramfs-4.13.13-300.fc27.x86_64.img
}
menuentry 'Fedora (0-rescue-4289f41d85794f5ebc59779ac5cdcc51) 27
(Workstation Edition)' --class fedora --class gnu-linux --class gnu
--class os --unrestricted $menuentry_id_option
'gnulinux-0-rescue-4289f41d85794f5ebc59779ac5cdcc51-advanced-dedb2196-1933-4fa3-b8bd-5123930308b9'
{
        load_video
        insmod gzio
        insmod part_msdos
        insmod ext2
        set root='hd0,msdos1'
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root
--hint-bios=hd3,msdos1 --hint-efi=hd3,msdos1
--hint-baremetal=ahci3,msdos1 --hint='hd0,msdos1'
9522bf8d-db18-48e9-a7d9-ae9c52d4343d
        else
          search --no-floppy --fs-uuid --set=root
9522bf8d-db18-48e9-a7d9-ae9c52d4343d
        fi
        linux16 /vmlinuz-0-rescue-4289f41d85794f5ebc59779ac5cdcc51
root=UUID=dedb2196-1933-4fa3-b8bd-5123930308b9 ro security=0
        initrd16 /initramfs-0-rescue-4289f41d85794f5ebc59779ac5cdcc51.img
}