I have not seen an instance where a GPU series that has been out for over 12 months has regressed in performance prior to an older one
Perhaps back in the very early accelerator days when everyone was making GPU-specific hacks of Quake 1 but even that was smoothed over by the transition to DirectX/OpenGL/GLiDE at the time
Perhaps back in the very early accelerator days when everyone was making GPU-specific hacks of Quake 1 but even that was smoothed over by the transition to DirectX/OpenGL/GLiDE at the time