With SWcursor set to "on", when running Beryl, the block (~ 64x64) where the mouse cursor resides will get corrupted, getting unexpected bits of graphics drawn under it.
This is a fundamental incompatibility between SW cursor and 3D acceleration. Is there any particular reason why you want to use SW cursor?
I think that, at some point, it helped avoid sudden hangs. There's much voodoo around it, so I can't give you a precise reason. In any case, maybe something sensible should be done with SWcursor is on, like disabling GLX and announcing it in the X log?
(In reply to comment #2) > I think that, at some point, it helped avoid sudden hangs. I think disabling silken mouse should be a better workaround for those.
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