It could still be compiz/unity7 falling back to software rendering incorrectly (which it has been known to do). This would not show up in the X or USC logs, but should be in .xsession-errors. However .xsession-errors is pretty empty compared to what it should look like.
Please run this command and attach the output here:
pmap `pidof compiz` | grep _dri
Please also look in /var/crash/ for crash files. And if you find a relevant one, please turn it into a bug report by running:
ubuntu-bug /var/crash/XXX.crash
Hmm, the logs don't show anything going wrong.
It could still be compiz/unity7 falling back to software rendering incorrectly (which it has been known to do). This would not show up in the X or USC logs, but should be in .xsession-errors. However .xsession-errors is pretty empty compared to what it should look like.
Please run this command and attach the output here:
pmap `pidof compiz` | grep _dri
Please also look in /var/crash/ for crash files. And if you find a relevant one, please turn it into a bug report by running: XXX.crash
ubuntu-bug /var/crash/