Just a quick post to save someone some faffing about.
I needed to coopt another computer into my render farm and had to use linux as it was made out of spare parts and had no OS. I'm not very Au fait with Linux.
I used Mint Linux 17.2 which installed very quickly and easily.
The thing that took me a few tries was getting the right driver for the graphics card: GTX560ti. Unless you use the right one there will be no CUDA option in the system preferences panel. This is where I wasted a lot of time.
It doesn't help that the version of Blender in the repository is so old: 2.69 (why do they do that - why not update it?). I believe I correct in saying that pre 2.70 Blender did not have built in CUDA support and after 2.70 it did. So for early versions you needed the CUDA toolkit now you don't. I downloaded 2.75a from Blender.org and extracted it into its own folder in my Home directory. I then started 'Driver Manager' by typing it in the search box in the start menu. I tried all the drivers:
the only graphics driver that worked - gave me the CUDA option in Blender - was version 3.04 (without updates - though I didn't try with updates and don't know what the 'updates' means.)
Next I wanted to install TightVNC to control it remotely like I do with my windows boxes. But VNC would not work with the OPENGL used in the blender interface and it started a separate session - So I ended up using Vino which comes with it preinstalled. . There is some info about using DCONF editor to set it up here. http://askubuntu.com/questions/589062/ubuntu-mate-where-is-vino-in-dconf
The last problem was using the box without a monitor. Easy on windows - nearly impossible on linux. There seemed to be a number of tutorials for VNC systems but none for Vino. Also I tried info from one site which said you can fool linux by putting a 75 ohm resister between one of the colour channels and ground. DO NOT DO IT!! - the red channel on one of the outputs on the graphics card now does not work.. not sure why. I am keeping it with a monitor attached.