i think your problem might be the monitor section, more precisely the syncing part; remove it. there is no need for it anyway, use dpms and try again.
X is capable of sorting out the supported modes itself, try to remove the modes section alltogether. what results do you get?
different m odules for the same hardware can interfere with ech other. try to start the 18.104.22.168-generic kernel and make sure no other graphics drivers has been loaded, before probing with X -configure.
the output of cat /var/log/Xorg.0.log | grep EE or | grep WW might be helpful.
btw. there is no 32bit depth; 32bit is really just 24bit (read that in some manual