Edit (05/2012): The information here may be outdated with the new Ubuntu releases. You may wanna take a look at Bumblebee instead of Ironhide
Okay after a day of trial and error and reading hundreds of forum posts in the internet I’ve finally found a way how to install Ubuntu 11.10 with working graphic enhancements and acpi on my system.
My system is a Inspiron 17R (N7110) and there’s a NVIDIA 525M with optimus technology in it (hate it). However, my processor: Intel Core i5-2410M CPU. Because I’ve read somewhere that it can provide problems, I’ve deactivated “USB Emulation” in the BIOS. I’m not sure tough if it affects anything.
Whatever I you do, I read now several times that you shouldn’t download an drivers from nvidia.com – use the repos describes in the text instead.
Put your USB, DVD or whatever in your computer and boot from it. When a keyboard and a body at the bottom of the screen appears, press F6 (if not it will boot without special config into live system).
After choosing your language, you click F6 and choose ACPI=OFF (this is necessary to boot up the installer).
2. Edit GRUB boot entry
At the first startup you’ll have to edit the GRUB boot entry manually. You select the default boot entry (Ubuntu smth.) and then you click edit. After “quiet splash” you add “pci=noacpi”. Ubuntu will boot up now, but you don’t want to change that with every bootup. As soon as you’re up, you go to a terminal and edit the file “/etc/default/grub” (sudo gedit /etc/default/grub).
To make the change permanent you change the GRUB_CMDLINE_LINUX_DEFAULT line to the following: GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash pci=noacpi”
After saving the file you can simply type in “sudo update-grub”. This will update the GRUB bootloader with it. Congratulations, you’ve got now a working system but without any 3D acceleration.
3. Install Drivers
First I’ve downloaded mesa-utils, just to make sure that I’ve got it I’m not sure if it is required.
sudo apt-get install mesa-utils
This will not bring you 3D acceleration yet. If you’ve got a NVIDIA driver, you have to download the driver for your card first. I’ve had some troubles with the drivers from the official NVIDIA site, but in some forums were solutions for that: Add the x-updates repository.
sudo apt-add-repository ppa:ubuntu-x-swat/x-updates
Now you update first your list and then you make an upgrade.
sudo apt-get update
sudo apt-get upgrade
4. Install Ironhide
Everything is prepared for the final step now. First you’ll have to add the repository from the ironhide guys.
sudo apt-add-repository ppa:mj-casalogic/ironhide
Update your sources:
sudo apt-get update
And then you can install ironhide:
sudo apt-get install ironhide
When the installation is done, it automatically starts ironhide-configuration. Go trough that tool, choose one of the profiles provided (I used the one on the top). There’ll be a window where you’ll have to select the NVIDIA card. It’s the one on the top (CRT-0). I have to admit I didn’t really understand why it asked that, but it worked with selecting CRT-0.
Now you just reboot your lightdm:
sudo restart lightd,
And you should see unity3D :)