I've installed Ubuntu 12.10 in my XPS 15 l521x. I had some issues (i.e. HidPoint is quite unstable for my Logitech wireless mouse/keyboard and works pretty randomly), but now the big one that is stopping me is that I'm unable to make my Mini Display-Port working.
I have a Mini DP to VGA (branded Apple) connected to an external monitor. The monitor is working and recognized in Windows 8, but there's no way I can make it work through Ubuntu (it doesn't even detect the display).
Honestly I'm running out of ideas and this functionality is necessary for me. Do you have any suggestion\advice that I can follow?
$ xrandr -q
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
LVDS1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm
1920x1080 60.0*+ 59.9 40.0
1680x1050 60.0 59.9
1360x768 59.8 60.0
800x600 60.3 56.2
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
$ lspci | grep -i VGA
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
01:00.0 VGA compatible controller: NVIDIA Corporation GK107 [GeForce GT 640M] (rev ff)