Ubuntu 20.04 - iMac late 2009. Nvidia Geforce 9400 freezes

Question

I have been trying to run Ubuntu 20.04 on an old iMac (late 2009). With a fresh install, it randomly freezes once resizing windows, changing the background wallpaper, or while opening a browser.

I have read a few posts describing the same problem, pointing to changing the graphics driver to the legacy-nvidia driver:

Help needed with Ubuntu 20.04 on iMac late 2009

Following the first part of the post:

sudo add-apt-repository ppa:kelebek333/nvidia-legacy
sudo apt update
sudo apt install nvidia-340
sudo reboot

It seems to work fine at first, however, I can't add the brightness control described in the linked topic. The monitor will stay black on the next reboot.

I have the same issue the monitor stays black after a few restarts.

Could you give a Linux beginner some pointers?

Answer 1

We have Ubuntu 20.04 working on a Late 2009 imac (in December 2021) and ran into these same kinds of issues but were able to successfully work through them. 3 things are critical in the install

1. The first critical point is that the install must be done on a BIOS partition (not an EFI one). I followed the "Option B" procedure in this post: https://ubuntuforums.org/showthread.php?t=2209602. You basically start with an EFI install procedure from the liveboot disk and then convert it to a BIOS one. If you do it on an EFI partition, you will have all kinds of problems with the video card, even if you install the right drivers. At least we did.

One minor point is 3/4 of the way down the page, you need to add "sudo" to one of the lines:

sudo mount --bind /dev /mnt/dev
sudo mount --bind /dev/pts /mnt/dev/pts
sudo mount --bind /proc /mnt/proc
sudo mount --bind /sys /mnt/sys
sudo chroot /mnt
sudo update-grub
exit

2. You need to install the proper NVIDIA drivers for the video card on your machine. For us, it was the NVIDIA "GeForce 9400". So you skip the last steps in the post in #1 above, and instead follow this second procedure here: Help needed with Ubuntu 20.04 on iMac late 2009. It looks pretty similar to what you tried, so I think maybe your problem is you didn't do step 1.

3. Finally, I installed mbpfan so the fans were not always running on high, using the procedure in this post. Imac with Ubuntu (Lubuntu 20.04) - Controlling fan speed

Yes, this may seem a bit tedious, but after installing a fresh 250GB SSD and with this Ubuntu 20.04 install procedure, our 2009 imac is running impressively well - almost too good to be true, really. The only remaining issue I have is I can't get it to suspend when on the login screen, but its such a minor issue compared to where the machine was before!!!