Stuttering / Frame drops with RS880/785G and AMD Bulldozer CPU

[Alex Deucher]

On Wed, Feb 8, 2012 at 7:03 PM, Shahar Or <mightyiampresence at gmail.com> wrote:
> Dear Ones,
>
> Since replacing an AMD Sempron 140 with an AMD FX-4100 CPU in my
> system I'm experiencing frame drops in practically anything. They seem
> to be CPU activity related and they are very frequent.
>
> I've reported this is bug #927918 in Ubuntu:
> https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/927918
>
> Please let me know if you think that this could be radeon driver
> related or something else because I really don't know where to
> start... I even looked at the AMD cache penalties bug:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/862583
> But it shouldn't make such a big noticeable problem, right?
>
> The BIOS is latest version. I've also tested FGLRX and that gives me
> low framerate in Ubuntu compiz so I'm not sure if there were frame
> drops.

Perhaps you didn't fully uninstall fglrx and reinstall the open source
driver.  Check the output of glxinfo and make sure you are not using
the software 3D driver.

Alex