Is my ATI graphics card supported in Ubuntu?
How can I install the ATI video card driver for Ubuntu 11.10?
Can someone please help me?
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The best driver, Gallium 3D, should automatically be enabled and installed.
Try running a 3D game like Neverball or Neverputt, you can find both in Ubuntu Software Center.
If they don't work install fglrx (not the post-release update) with Additional Drivers in System Settings.
This steps worked for me and what you probabably should do is upgrade you ATI drivers. They have solved a lot of those issues you're facing on.