Hi all,

I installed ubuntu 12.10 on my mac book pro 8,2 using the normal installer of the amd64+mac release (ubuntu-12.10-desktop-amd64+mac.iso). The installation works pefectly, but in order to be able to use the intel graphic card in place of the RADEON, I have to make the EFI boot. Using "boot-repair" I installed Grub-efi, and using rEFInd I managed to get to the grub-efi menu.

The problem is that during X initialzation I get a message saying that X cannot be start.
I attach here the fundamental part of Xorg log:

[ 13.417] (II) intel(G0): Creating default Display subsection in Screen section
"Default Screen Section" for depth/fbbpp 24/32
[ 13.417] (==) intel(G0): Depth 24, (--) framebuffer bpp 32
[ 13.417] (==) intel(G0): RGB weight 888
[ 13.417] (==) intel(G0): Default visual is TrueColor
[ 13.417] (--) intel(G0): Integrated Graphics Chipset: Intel(R) Sandybridge Mobile (GT2)
[ 13.417] (**) intel(G0): Relaxed fencing enabled
[ 13.417] (**) intel(G0): Wait on SwapBuffers? enabled
[ 13.417] (**) intel(G0): Triple buffering? enabled
[ 13.417] (**) intel(G0): Framebuffer tiled
[ 13.417] (**) intel(G0): Pixmaps tiled
[ 13.417] (**) intel(G0): 3D buffers tiled
[ 13.417] (**) intel(G0): SwapBuffers wait enabled
[ 13.417] (==) intel(G0): video overlay key set to 0x101fe
[ 13.417] (II) intel(G0): Output VGA1 has no monitor section
[ 13.418] (II) intel(G0): Output HDMI1 has no monitor section
[ 13.468] (II) intel(G0): Output DP1 has no monitor section
[ 13.468] (II) intel(G0): EDID for output VGA1
[ 13.468] (II) intel(G0): EDID for output HDMI1
[ 13.516] (II) intel(G0): EDID for output DP1
[ 13.516] (II) intel(G0): Output VGA1 disconnected
[ 13.516] (II) intel(G0): Output HDMI1 disconnected
[ 13.516] (II) intel(G0): Output DP1 disconnected
[ 13.516] (WW) intel(G0): No outputs definitely connected, trying again...
[ 13.516] (II) intel(G0): Output VGA1 disconnected
[ 13.516] (II) intel(G0): Output HDMI1 disconnected
[ 13.516] (II) intel(G0): Output DP1 disconnected
[ 13.516] (WW) intel(G0): Unable to find connected outputs - setting 1024x768 initial framebuffer
[ 13.516] (II) intel(G0): Using default gamma of (1.0, 1.0, 1.0) unless otherwise stated.
[ 13.516] (II) intel(G0): Kernel page flipping support detected, enabling
[ 13.516] (EE) intel(G0): No modes.
[ 13.516] (II) UnloadModule: "intel"
[ 13.516] (EE) Screen(s) found, but none have a usable configuration.
[ 13.516]
Fatal server error:
[ 13.516] no screens found
[ 13.516] (EE)
Please consult the The X.Org Foundation support
at http://wiki.x.org
for help.
[ 13.516] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[ 13.516] (EE)
[ 13.519] Server terminated with error (1). Closing log file.
Looking at dmesg, I found this error:

[ 12.741598] i915 0000:00:02.0: >irq 47 for MSI/MSI-X
[ 12.741610] [drm] Supports vblank timestamp caching Rev 1 (10.10.2010).
[ 12.741611] [drm] Driver supports precise vblank timestamp query.
[ 12.741620] i915 0000:00:02.0: >Invalid ROM contents
[ 12.741622] [drm] failed to find VBIOS tables
Googling around I noticed various suggestions about adding lines such as "i915.modeset=0" "radeon.modeset=0" etc to the kernel line in grub, but they seems not to have any effect. By the way, the relevant part of grub.cfg goes like this:

gfxmode $linux_gfx_mode
insmod gzio
insmod part_gpt
insmod ext2
set root='hd0,gpt5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt5 --hint-efi=hd0,gpt5 --hint-baremetal=ahci0,gpt5 22f63917-22e5-41e0-a525-26a42c30a77f
else
search --no-floppy --fs-uuid --set=root 22f63917-22e5-41e0-a525-26a42c30a77f
fi
echo 'Loading Linux 3.5.0-17-generic ...'
linux /boot/vmlinuz-3.5.0-17-generic root=UUID=22f63917-22e5-41e0-a525-26a42c30a77f ro no-splash $vt_handoff
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-3.5.0-17-generic
from where you can also infer the kernel version that I'm using (that I got from ubuntu repository).
What do I need to do in order to make X initialize?

Thank you!