Always try to follow version 1 of install, it should work, also I have another clipmark about a possible lib file missing and how to correct it for the newest card and the driver at the repo

By the way, you can open a terminal (for see some stdout info printed by the apps, specially glxinfo) and execute 1 of the following apps (they are normally installed in Ubuntu):

glxdemo
glxgears
glxheads
glxinfo

In glxinfo see the line that say something like:
direct rendering: Yes

If it say yes, then you are done.

remember reinstall the drivers with each kernel upgrade