Ttgjyuk

I tried switching to the proprietary AMD/ATI drivers using the Software Center > Edit > Software Sources > Additional drivers window in 14.04, which left me with a scary black-as-the-night screen after reboot. I could not even open the text only console.

Using a live cd, I chroot-ed in and ran sudo apt-get remove --purge fglrx* and in my nervous haste may have installed ubuntu-drivers-common (I don't know/remember if it was already installed).

I assume I've reverted back to open source because my display is working again, but I'm not sure...

When I open the Additional drivers window, all options (xserver-xorg-video-ati, fglrx-updates, and fglrx) are greyed out and can't be selected! And now there is a new option selected, "Continue using a manually installed driver."

When I run ubuntu-drivers list I get the following output:

fglrx-updates
fglrx

So, what's going on? Using sudo apt-get remove --purge fglrx* says everything is gone.

When I run ubuntu-devices I get the following output:

model : Radeon HD 6970M
vendor : Advanced Micro Devices, Inc. [AMD/ATI]
manual_install: True
modalias : pci:v00001002d00006720sv0000106Bsd00000B00bc03sc00i00
driver : fglrx - distro non-free
driver : xserver-xorg-video-ati - distro free builtin recommended
driver : fglrx-updates - distro non-free

I believe the problem is manual_install is set to True. I don't know if I'm actually using the open source driver, I don't know why the driver options are greyed out, I don't know how to set manual_install to False.

I don't have any backup xorg.conf files in /etc/X11 (although I do have a xorg.conf.failsafe there - is that a backup?) and the "revert" button is greyed out in the Additional drivers window.

I just want to go back to the way things were (open source driver selected and automatically updates).

Extra info: The reason I changed drivers was because sometimes after trying to awake Ubuntu from sleeping (especially after long periods asleep)... well, it doesn't. It stays at a black (grey) screen. Searching seems indicate it's a known bug.

This solution worked for me :

sudo apt-get purge "fglrx.*" # remove proprietary drivers
sudo rm /etc/X11/xorg.conf # remove old Xserver config

reinstall open source drivers

sudo apt-get install --reinstall xserver-xorg-core libgl1-mesa-glx:i386 libgl1-mesa-dri:i386 libgl1-mesa-glx:amd64 libgl1-mesa-dri:amd64

sudo dpkg-reconfigure xserver-xorg # reconfig Xserver

sudo reboot

this will give you working video drivers and your driver options will no longer be greyed out

Hello I got the solution is actually simple.

Run following command in terminal:

sudo apt-get autoremove xserver-xorg-video-ati
sudo apt-get install xserver-xorg-video-ati

You will get a notification for restart your computer, restart your computer and your problem has gone.