utopic + lightdm 1.11.8 + nvidia-331 (newest): black screen (nvidia-331 has a nvidia-prime error, so the 'nouveau' fallback is used)
utopic + gdm boots well with 'nouveau' only
nvidia-331 report lp:1366284
utopic + lightdm 1.11.8 + nvidia-331 (newest): black screen (nvidia-331 has a nvidia-prime error, so the 'nouveau' fallback is used)
utopic + gdm boots well with 'nouveau' only
nvidia-331 report lp:1366284