Comment 51 for bug 413259

As I am also affected by this bug with that same ATI Radeon 9600 Mobility, I would like to add some experiences I made with kms and the 9.10 kernel.

After multiple karmic installations with ATI GPU's, I was surprised to see this bug with my ATI Radeon 9600 Mobility. I also suffered from performance problems with that Radeon 9600 Mobility without kms enabled (regression 9.04 --> 9.10).

Following the advice posted here I get best performance using kms and forcing the card in pci mode.

My card setup is done via a radeon.conf in /etc/modprobe.d/ with the following two lines:

options radeon agpmode=-1
options radeon modeset=1

(Don't forget to run 'sudo update-initramfs -u -k all' after you made the changes.)

Other ATI devices like the FireGL V3200 Mobility (IBM ThinkPad T43p) or even a normal Radeon 9600 (Desktop computer) are not affected by this bug. I would rather say that I have some quiet decent performance with these cards (kms enabled). A little bit more problems with my ATI x1250, but the performance of the x1250 is getting better and better too, and the card is not affected by this bug...

Following the advice posted in this bug I get best performance using kms and forcing the card in pci mode.

Don't forget to run 'sudo update-initramfs -u -k all' after you made the changes.

Kudos to all the people that work on the new ATI driver, as the OpenSource driver generally performs better than the fglrx driver ever did, when I used it on that HP/Compaq nc8000... ;)