GRUB 2 error – "fb: switching to radeondrmfb from EFI VGA"
There seems to be a problem with the radeon driver when booting. You can test a fix by doing this:
- When you see the grub menu, press 'e', which will allow you to edit the entry.
- Go to the line with "linux...." and look for where it says 'ro'.
- After the 'ro', add 'nomodeset' (without quotes), and then boot (press F10).
If that works, you can make it permanent by editing your /etc/default/grub file, and changing the line to look like this:
GRUB_CMDLINE_LINUX="nomodeset"
Then run:
sudo update-grub
This isn't the best solution, since it seems to put your machine into software rendering. I'm hunting for a proper fix.
Once in GRUB press the e key. We’re now going to disable the AMD graphics card while we boot into the Ubuntu Live CD. Look for the line set gfxpayload=keep. Once you’ve found it, type the following lines underneath to disable the AMD graphics card:
outb 0x728 1
outb 0x710 2
outb 0x740 2
outb 0x750 0
Next find the kernel line and after “quiet splash” , add the following
i915.lvds_channel_mode=2 i915.modeset=1 i915.lvds_use_ssc=0
Source: https://orville.thebennettproject.com/articles/installing-ubuntu-14-04-lts-on-a-2011-macbook-pro/
If you have a graphics card in pull it out and use the integrated graphics controller. If you dont have an integrated one try another card.