I've just downloaded Ubuntu Desktop 16.04.02 LTS and made a fresh install.
Step by step, how should I install the NVidia driver + CUDA?
VGA compatible controller: NVIDIA Corporation GK106 **[GeForce GTX 660]** (rev a1)
I haven't tried to install the NVidia driver at all, yet. Apart from updating, I have only dowloaded Blender 2.78c from blender.org and manually extracted it to my home folder, and I have installed FlightGear 2017.1.2 from an additional repository.
With both applications, the desktop freezes permanently just a few seconds or a few minutes after startup, except for the mouse cursor. Maybe it's the Nouveau driver, I don't know and I'm not addressing that issue here, either, because I need CUDA anyway.)
It's not a UEFI machine => maybe more chances.
I went to the NVidia support website in order to see what version it is.
I also downloaded the .run NVidia file but did not launch it, instead I installed the corresponding package:
sudo apt install nvidia-375
The installation procedure finished with no apparent accident and I got the terminal prompt back.
Maybe I should have issued the command which is reported to be critical in various threads:
Well, I didn't, not to risk messing up with the installation procedure in case it had been fixed by now to a fully automatic procedure.
First reboot => boot manager OK, then the LUKS pass phrase input field appeared but my input was not being displayed with bullet chars as usual. Ctrl-alt F1...F6: black screen. Ctrl-alt F7: black screen with my passphrase on the top line.
Second reboot => boot manager OK, then not even the LUKS passphrase input screen, just black screen, ctrl-alt F1...F7 => black screen.
I'm going to reinstall from scratch right now then give it another try issuing that further
nvidia-xconfig command after installing the package.