First of all I wanted to say that I am pretty new to Linux, but I admire the system a lot!
Ok, so after having ubuntu 13.04 for a week, I was experimenting with compiz cube effects and the system crashed. After rebooting I had the following error "System is running in low graphics mode". I tried several solutions posted on the net and finally installing gdm solved the problem. However not entirely. At the moment I do not have this error anymore, but the graphic is not working perfectly. The autohide unity launcher leaves the gray space (the wallpaper is not stretched to that area). The transparancy of the pannels doesnt work anymore and the worst thing I noticed is much higher usage of CPU.
Basing on the above I am thinking that the graphics driver doesnt work properly. Is that correct?
Now my hardware: I have Lenovo IdeaPad y580 laptop with i7 processor, intel built-in graphic card and GeForce 660M. I know that this works under this Optimus technology, thus first day of having Ubuntu I installed Bumblebee, which was working ok (there was a significant difference in FPS between glxspheres and optirun glxspheres). However I did not configurate any application to work with this optirun command, so I am thinking that everything (unity, cairo dock (no openGL), compiz) was using this Intel Video Card.
Could you please give me any advice how to solve these problems? Am I thinking correctly that it must be something with the Intel driver? Should I be using Geforce for compiz effects or cairo dock (if so, how?).