I just got a Samsung NP300E5A notebook with Nvidia Optimus. Following other answers, I installed Bumblebee and after some troubleshooting (followed https://github.com/Bumblebee-Project/Bumblebee/issues/220) I finally get this:
desktop:~$ glxinfo | grep OpenGL OpenGL vendor string: Tungsten Graphics, Inc OpenGL renderer string: Mesa DRI Intel(R) Sandybridge Mobile OpenGL version string: 3.0 Mesa 8.0.2 OpenGL shading language version string: 1.30 OpenGL extensions: desktop:~$ optirun glxinfo | grep OpenGL OpenGL vendor string: NVIDIA Corporation OpenGL renderer string: GeForce GT 520MX/PCIe/SSE2 OpenGL version string: 4.2.0 NVIDIA 304.37 OpenGL shading language version string: 4.20 NVIDIA via Cg compiler OpenGL extensions: optirun glxspheres Polygons in scene: 62464 Visual ID of window: 0x21 Context is Direct OpenGL Renderer: GeForce GT 520MX/PCIe/SSE2
It seems OK then, but if I try to dim the screen (or if I go on batteries and it tries to do so automatically) it doesn't seem to be able to do it and almost freezes (eats up so much CPU that I cannot even shutdown properly).
In another forum I saw somebody with the same problem and no help (https://answers.launchpad.net/ubuntu/+source/xserver-xorg-video-nv/+question/205823)
Update: Following this (http://ubuntucomputing.blogspot.com.br/2011/10/how-to-fix-adjust-screen-backlight-of.html#comment-form) I improved it a litle by editing /etc/default/grub for
GRUB_CMDLINE_LINUX_DEFAULT="splash acpi_backlight=vendor" GRUB_CMDLINE_LINUX="acpi_backlight=vendor"
and runing 'update-grub'. However, now I can dim the screen but I cannot get it all the way up again!. Is it perhaps related to something different than bumblebee? (I do not know)
Any idea please please?