During installation of Ubuntu on a Mac I encountered some video problems that others have already solved, but I found the solutions only after a few hours of digging here and there. So below is an approach to these problems scraped together in one place:
I did a de novo installation of 12.04 on a G4 “iLamp” (nvidia video card) using the alternate installation CD (because video did not work with the live CD). Upon first boot, the monitor displayed only a shifting pattern of purple and gray shadows, usually confined to only part of the screen, with the rest blank. I'll leave the technical explanation of this phenomenon to more competent voices, but it seems to have something to do with KMS. KMS can be gotten around by adding at the “boot:” prompt “Linux nouveau.modeset=0”, but the result is an unusable, psychedelically colored desktop (a problem with color depth, apparently). I tried many similar parameters at the boot prompt, but none, alone or in combination, yielded a usable interface, except "Linux single nouveau.modeset=0" This produced a text-only console, and a fighting chance of fixing the machine.
The fix that yielded a normal graphical desktop was to compile and install the nv driver, and blacklist and delete the nouveau driver, a procedure that is detailed at http://wiki.freegeek.org/index.php/Linux_PPC_Testing (many thanks to the authors!) It is reproduced below for your convenience:
Some caveats:
Regarding the step:
The author is discussing his 12.04 installation, but he specifies adding to /etc/apt/sources.list references to natty's repositories. That's not a mistake. From what I can tell, the source for the nv driver is not available in 12.04's repositories; you have to get it from natty's.
Regarding the step:
This must be done. Apt will want to also remove xserver-xorg-videoall. Sounds scary. It must also be done.
Regarding the step:
“The Ubuntu Way” seems to be to add “blacklist nouveau” to /etc/modprobe.d/blacklist.conf
The above done, I now have a nice Unity-2D desktop. From my perspective, i.e., that of a knuckle-dragging end-user, I wonder if this issue could be handled a bit better by the powers that be. Nouveau is not up to the job yet, but neither an nv package nor nv's source is available from the standard repositories. Seems like a situation that could be substantially improved without a lot of trouble.
I did a de novo installation of 12.04 on a G4 “iLamp” (nvidia video card) using the alternate installation CD (because video did not work with the live CD). Upon first boot, the monitor displayed only a shifting pattern of purple and gray shadows, usually confined to only part of the screen, with the rest blank. I'll leave the technical explanation of this phenomenon to more competent voices, but it seems to have something to do with KMS. KMS can be gotten around by adding at the “boot:” prompt “Linux nouveau.modeset=0”, but the result is an unusable, psychedelically colored desktop (a problem with color depth, apparently). I tried many similar parameters at the boot prompt, but none, alone or in combination, yielded a usable interface, except "Linux single nouveau.modeset=0" This produced a text-only console, and a fighting chance of fixing the machine.
The fix that yielded a normal graphical desktop was to compile and install the nv driver, and blacklist and delete the nouveau driver, a procedure that is detailed at http://wiki.freegeek.org/index.php/Linux_PPC_Testing (many thanks to the authors!) It is reproduced below for your convenience:
Code:
Following some advice I added to my /etc/apt/sources.list file:
deb http://ports.ubuntu.com/ubuntu-ports/ natty universe
deb-src http://archive.ubuntu.com/ubuntu natty universe
Then I updated and grabbed the tools I'd need to compile the driver:
sudo apt-get update
sudo apt-get install build-essential fakeroot dpkg-dev
So then, just for funsies sake, I made a directory in my home dir to dump all of the items into:
mkdir nv-build
cd nv-build
So then it was time to grab the source:
apt-get source xserver-xorg-video-nv
And then I began to build it:
cd xserver-xorg-video-nv-2.1.17
sudo apt-get build-dep xserver-xorg-video-nv
dpkg-buildpackage -rfakeroot -b
It all seemed to go perfectly from there and whipped the package together surprisingly fast to I went ahead and gave it a try:
cd ..
sudo dpkg -i ./*.deb
I removed those entries I made in the sources.list and I was almost good to go! So to avoid any complications, I did two more things; for starters, I removed the nouveau driver:
sudo apt-get remove xserver-xorg-video-nouveau
<snip>
And then I blacklisted nouveau kernel entries from modprobe by making /etc/modprobe.conf and adding this line to it:
blacklist nouveau
Saved that and rebooted into my fancy new and much faster nv setup!!Regarding the step:
Code:
deb http://ports.ubuntu.com/ubuntu-ports/ natty universe
deb-src http://archive.ubuntu.com/ubuntu natty universeRegarding the step:
Code:
sudo apt-get remove xserver-xorg-video-nouveauRegarding the step:
Code:
And then I blacklisted nouveau kernel entries from modprobe by making /etc/modprobe.conf and adding this line to it:
blacklist nouveauThe above done, I now have a nice Unity-2D desktop. From my perspective, i.e., that of a knuckle-dragging end-user, I wonder if this issue could be handled a bit better by the powers that be. Nouveau is not up to the job yet, but neither an nv package nor nv's source is available from the standard repositories. Seems like a situation that could be substantially improved without a lot of trouble.