Hmm, maybe my hypothesis is wrong. However, these test packages from the PPA use gallium drivers as default instead of the classic drivers, and I am less confident about my fix for gallium, so please test classic this way:
After installing the packages:
cd /usr/lib/
sudo mv dri dri-gallium
sudo mv dri-classic dri
and then log out and in again.
Hmm, maybe my hypothesis is wrong. However, these test packages from the PPA use gallium drivers as default instead of the classic drivers, and I am less confident about my fix for gallium, so please test classic this way:
After installing the packages:
cd /usr/lib/
sudo mv dri dri-gallium
sudo mv dri-classic dri
and then log out and in again.