At the moment ATI Radeon HD6470 hasn't working proprietary driver. Open source driver works not well too: the card heats and cooler works very loud and notebook becomes hot. I would like to use integrated Intel's video card until this problem be solved, but I don't know how to switch to it and if it will work well with external monitor through VGA port.
my case: Thinkpad T500: ATI HD3650 -> Intel
If you have not yet resolved your problems you could try the solution outlined here by user Nick Andrik. This is the only thing that has worked for me after 6 months of searching and trying all sorts of solutions.
"For those who have hybrid systems (ATI/intel) and fglrx has stopped working in 12.10, then the problem might be like the one described here (fglrx incompatibility with the recent version of the intel driver): https://bugs.launchpad.net/ubuntu/+source/fglrx-installer-updates/+bug/1068404
What I would suggest would be
Remove all the fglrx* packages:
sudo apt-get purge fglrx*
Add my PPA in your repositories list:
sudo add-apt-repository ppa:andrikos
Update your package information:
sudo apt-get update
Update the fglrx and intel drivers:
sudo apt-get install fglrx xserver-xorg-video-intel
Don't forget to enable the fglrx driver
sudo aticonfig --initial --force"