I'm running this project on Ubuntu64b bit, client 6.3.5 (I'll upgrade to 6.3.8 when I come back from Portugal) and the most important thing:

Driver Nvidia 173.14.12 installed with Envy-NG.

So driver version 177.xx (a pain in the ass to install manually) are NOT necessary.

Fun thing is that in System -> Administration -> Drivers they are not shown (it's like the system is running on non-Nvidia drivers)