ATI X1300 Pro Slower in 10.04 than 9.04

[jelofson]

Just did a fresh install of 10.04. I am using the Ati opensource driver. I noticed in a game that I was getting significantly lower frame rates now. Actually about 1/2 that of 9.10

Anyone thing of a reason for that? I was using the opensource driver in 9.10 too. glxgears gives 1/2 the fps I used to get.

I did search around a bit to see if I could find any answers.

Thanks,

[jelofson]

Found out that this is related to the Kernel Mode Setting (KMS) and ATI drivers in 10.04

http://www.phoronix.com/scan.php?pag...u_kmsums&num=1

To fix this (temporarily) I added an option to my boot menu. I have dual boot so it was easy to get to the the grub boot screen and edit the main entry.

The boot option I set was
radeon.modeset=0

https://help.ubuntu.com/community/BootOptions

I hope this helps someone else.
I believe you have to do this each boot, or there are other options too.

Jon

[insaini]

I just figured this out myself..

you can edit /etc/default/grub

add 'nomodeset' to the kernel options .. standard options are 'quiet splash' .. so make it 'quiet splash nomodeset'

then exit and do an sudo update-grub..


its a fix .. you wont get plymouth on startup but atleast you can login..

[boombox1387]

I just figured this out myself..

you can edit /etc/default/grub

add 'nomodeset' to the kernel options .. standard options are 'quiet splash' .. so make it 'quiet splash nomodeset'

then exit and do an sudo update-grub..


its a fix .. you wont get plymouth on startup but atleast you can login..

Thanks so much for this! 3d/composited graphics were rendering so slowly that my computer was unusable unless I switched to Metacity, but I was finding it really hard to live without Compiz. (I need my screen corner shortcuts!) Turning off KMS seemed to fix things on my Radeon x1300.