How to install nvidia optimus driver?

I have followed http://ubuntuportal.com/2012/01/bumblebee-3-0-tumblewed-nvidia-optimus-gpu-switching-for-linux-has-been-released-how-to-install-bumblebee-3-0-on-ubuntu.html this guide to install nvidia driver on my Dell Inspiron N5110 notebook (Intel HD Graphics 3000 + NVIDIA GeForce GT525M), but i always get some error while i want to start any program with the optirun command.

Terminal says:

adam@Adam-LT:~$ optirun firefox
[ 1482.559417] [ERROR]Cannot access secondary GPU - error: Could not load GPU driver

[ 1482.559517] [ERROR]Aborting because fallback start is disabled.

My laptop cooler always cools the laptop, which means that nvidia card is consuming power in the background. (Terminal sometimes says something daemon-server is not running.) Can you give me some solution for this?

I recently had this problem as well.

For me, all I had to do was run the following commands. I'll break them down:

sudo apt-get install ppa-purge
sudo apt-get purge bbswitch-dkms bumblebee-nvidia

That installs the PPA-Purge utility and removes BBSwitch and Bumblebee

sudo apt-get install linux-headers-generic

That installs the proper Linux headers. For some reason, BBSwitch wouldn't (for lack of a better word, insert) itself into the kernel.

Then a simple

sudo apt-get install bbswitch-dkms bumblebee-nvidia

fixed everything. Oh, and a reboot, of course :)

Hopefully this will help you at least a little bit! Please let me know how you go

On an upgrade from Ubuntu 12.04 to 12.10 it is logical that bumblebee has been installed before. The PPA however becomes disabled on the upgrade, so you will need to enable it again!

sudo add-apt-repository ppa:bumblebee/stable
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install bbswitch-dkms bumblebee-nvidia

At this moment the new version of bumblebee will be installed as well as nvidia-current as it is a dependency of bumblebee-nvidia.

If your home directory is encrypted the installation process will hang at update-initramfs. This can be solved by disabling FRAMEBUFFER=y in /usr/share/initramfs-tools/conf-hooks.d/cryptsetup

# This will setup non-us keyboards in early userspace,
# necessary for punching in passphrases.
KEYMAP=y

# force busybox on initramfs
BUSYBOX=y

# and for systems using plymouth instead, use the new option
# FRAMEBUFFER=y  # DISABLED to install nvidia drivers

Now optirun works perfectly on my system, Geforce GT 650M, on an Asus N56V.