I have a Lenovo ThinkPad edge e531 laptop that dual boots windows 7 and Ubuntu 14.04. Prior to upgrading to 14.04 I was using bumblebee in order to utilize my nvidia gpu (Nvidia GeForce 740M). In 14.04 I read somewhere that it was better to use prime and switch easily between the two graphic cards at any time.
So I tried installing nvidia 331, 337 and all other versions between 331 and 337 that automatically came with prime installed, but I encountered the following problem:
Once the nvidia driver is installed, the laptop starts using the nvidia card exclusively and when I switch back to my Intel card I can no longer open nvidia settings and I can no longer switch back to my nvidia card. This is what I get when I try to launch nvidia settings from the terminal:
** Message: PRIME: Requires offloading ** Message: PRIME: is it supported? yes Segmentation fault (core dumped)
I tried everything (installed prime indicator, tried with different version of nvidia driver), but to no avail. Any help will be greatly appreciated! Thank you.