Kaleidoscope CAD - Imac screen crazies??

[Anonymous]

My Imac is developing very strange kaleidoscope style crazy coloured patterns on screen; It makes it impossible to continue in AchiCAD; Some sort of graphics fang; I do recall seeing a subject on same issue on Imac's; Apparently not solve with latest OS update with MAc; Can anyone help on the subject? BTW- it is not limited to ArchiCAD afterwards.

[Thomas Holm]

It's a known issue with certain ATI graphics chips on iMacs and MacBookPros from 2006-2007. It's not limited to Archicad, but it seems Apple has been unable to fix it as of OSX10.5.6. Since it's been so long, and no complete fix yet, I'm guessing it's a hardware issue that can't be fixed with a driver upgrade. Try this workaround:
http://archicad-talk.graphisoft.com/viewtopic.php?p=139674#139674