Lubuntu sits with a blank screen for more than a minute after switch on while it is booting to the desktop.
to get the old fashioned verbose mode back, edit:- /etc/default/grub
gksudo pico /etc/default/grub
GRUB_TIMEOUT=10 #change from 10 to 0
Delete (or comment out) the whole line which contains 'quite splash'
uncomment the line GRUB_TERMINAL=console
save the file, then at the command line, do:
sudo update-grub
and restart