Generally this is caused by not having an appropriate driver for your chipset[s] in xorg.conf, or that your chipset[s] is/are not supported by any of the drivers. Post your Xorg.0.log located here: /var/log/Xorg.0.log and the xorg.conf file that you're using, and set the status back to new here.
** Changed in: lightdm (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1258466 Title: lightdm does not start on amd apu nb Status in “lightdm” package in Ubuntu: Incomplete Bug description: after fresh instal i've got a white screen. Been able to boot to cmd line after editing grub to nomodeset. ProblemType: Bug DistroRelease: Ubuntu 13.10 Package: lightdm 1.8.4-0ubuntu1 ProcVersionSignature: Ubuntu 3.11.0-14.21-generic 3.11.7 Uname: Linux 3.11.0-14-generic x86_64 ApportVersion: 2.12.5-0ubuntu2.1 Architecture: amd64 Date: Fri Dec 6 12:32:35 2013 InstallationDate: Installed on 2013-12-06 (0 days ago) InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1) LightdmConfig: [SeatDefaults] autologin-guest=false autologin-user=lina autologin-user-timeout=0 autologin-session=lightdm-autologin MarkForUpload: True ProcEnviron: TERM=linux PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=lt_LT.UTF-8 SHELL=/bin/bash SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1258466/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp