have an iMac G4
This machine have:
PowerPC 7441 CPU with Vector Unit (G4), 64K L1 Cache, 256K L2/L3 Cache.
1024 MB RAM (133 MHz),
200 GB IDE Harddrive,
nVidia GeForce 2MX/400 with 32 MB VRAM.

I hav just set it up with Ubuntu 9.04 "Jaunty Jackalope".
Everything runs pretty smooth(far greater than my expectations that is, I would compare ith with running Ubuntu on a P4).

My only issue is that Compiz Fusion (desktop effects) won't be actiavated.
This is of course baceause nVidia is too lazy to compile their proprietary binary-only driver for anything other than the o-migthy x86/x64.
Therefore I am locked to running a simple, standard framebuffer driver, which of course dont provide either 2D or 3D acceleration. (I get about 25 FPS running glxgears with framebuffer driver).

Is it anyone who might know if there exist an open driver for this card, which provide accelerated 3D, or at least accelerated 2D? Because now the GUI is far away from running as smooth as I am used to.

I tried to install the free driver, nouveau. But I got some weird error messages (is seems it just froze while compiling the kernel module). I tried to install it both through apt-get, and synaptics. And anyways, this "nouveau" driver does not yet as of current date officially support 3D..

Therefore the nouveau team wont provide any documentations on how to actiave the experimental 3D support in the driver.

I really would like to still be able to run Ubuntu on my dated iMac, as Mac OS X just wont do it for me. But as long as the GUI is so slow as it is right now, it is not pleasing. Far away from the Ubuntu experience I am used to, and believe me, I have runned Ubuntu on a lot of different setups, mostly x86/x64 though.

I think it also might be possible to run a compositing X session witch is CPU accelerated rather than GPU accelerated, but I am really concerned this would impact hard on the CPU, if not just strangle the CPU completely. (remember this is in fact a single core, 32-bit processor from 2001).

And, a little bit off topic. I have problems activating Desktop Effects on an iMac G3 with an ATI Rage 128 card, even though I know the free ATI driver support this card with 3D accelerations, any suggestions here?
If there is anyone who could help me with my issues, I would really appreciate it!