I am running Ubuntu 14.04 alongside windows 8.1 on an HP Envy 15 laptop having Nvidia gtx 850m graphic card. I was trying to setup the cuda programming environment as given here
in the Ubuntu text only mode (obtained by the Ctrl+Alt+F1 combination)
For the cuda installation file, I downloaded the
cuda_7.0.28_linux.run for ubuntu 14.04. When I executed the file, it reported some error (which I don't remember). However, on searching online, I found a solution which asked to stop the
lightdm service and then execute the file. I did so and the installation worked perfectly fine. However, I did not restart the
lightdm service and tried to switch from the ubuntu text mode to the GUI mode. On pressing the combo
Ctrl+Alt+F7 the screen went dark with a cursor blinking on left hand top. After waiting for a while, I forced shutdown using the power button.
When I rebooted, I was stuck in the Ubuntu login loop problem. After extensive searching , I tried the following steps
a) dpkg reconfigure lightdm
b) remove and reinstall lightdm
c) install gdm and set it as default manager (for the concerned process)
However, none helped.
But after certain attempts, even the login screen stopped appearing. Now there is a black screen with a cursor on left hand top. After a few seconds, the screen seemingly refreshes and again the cursor starts blinking.
Now, is there any solution by which I get my ubuntu working without having to reinstall a fresh copy? Please help!!