I'd see if OF remains working OK if left alone for those 20 minutes or so. Do get the Apple HW diagnostics CD and run it. This looks like a hardware problem to me. Last time I've seen artifacts like those (on a PowerBook) the GPU needed reballing.

Also: open a shell and run 'memtest vmem'.

[ Edited by jacadcaps 04.07.2026 - 16:30 ]