Yeah...that guide worked for me too...I'm on ATI x1270...it doesn't even get mentioned on ATI's website so forget the drivers (even for windows).
However considering what pains you have gone through, I'm lucky!...I'm atleast getting 3-d though at 1/5th the pace and very much buggy!...but it is usable.
Lets see what those proprietary drivers can do for me.
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