CUDA on laptop with 14.04


I have a question about CUDA on a Laptop with Ubuntu 14.04. I am trying to make CUDA work on my computer and after 7 formats and about 36 hours I am out of any ideas. My problem is, whenever I try to install CUDA it comes with Nvidia driver 346.46. I install the driver, I reboot the computer , I set the CUDA, I make the samples files and run them, they all work perfectly. But as soon as I turn off the computer and try to startup again, I am stuck at splash screen. The “getting stuck” part happens so quickly, I had to reboot the computer about 50 times to just see what the problem was. Apperantly the system gets locked at “Resolver State [OK]”. After this line it freezes and I can’t do anything. I have troubleshooted the problem and it seems to be connected to graphics card driver. From what I read, I have to revert the graphics driver, delete everything related to nvidia and install xorg stuff (which I can’t do since the computer freezes in 1-2 seconds as soon as I see the logo screen).

What I understand from CUDA is, when it installs 346.46 driver, it takes place of Xorg driver. Because from the additional driver screen, the Xorg driver option is selected. When I run the terminal code however and from the Nvidia Settings screen, I can see that the computer is using the 346.46 driver. And I cannot change the driver from the additional driver screen as well. Whenever I click on say 331 driver it just instantly reverts back to 346. And as soon as I try to reboot the computer, the computer basically crashes and I have to install a clean Ubuntu, because I cannot see any kind of terminal nor any combination of key seems to open one. In the meanwhile I can perfectly use the 331 driver at the moment. I can change back to xorg, change to 331 back, turn off the computer, turn on. No problem at all. But as soon as I install 346 driver, everything goes nuts.

My graphics card is a gt740m, processors is an i7 and the computer is a Lenovo z510 laptop.